Interactive Fiction
and Natural
Language
Processing
David J. Snyder
1
What is Interactive Fiction?
“Interactive fiction, often
abbreviated as IF, is a simulated
environment in which players use
text commands to control
characters.”
Wikipedia, the free encyclopedia
http://en.wikipedia.org/wiki/Interactive_fiction
April 5, 2005
Best known example is a series
of “text adventure games”
produced by a company called
Infocom in the 1980s.
2
The classic example is
ZORK
ZORK has been made available as freeware by
Activision, the current owner of the Infocom
properties, and is available for download at
http://www.infocom-if.org/downloads/downloads.html
3
A Short History
All IF has one common ancestor- the game ADVENTURE.
“In 1975, Will Crowther wrote the first text adventure game, Adventure. It was
programmed in Fortran for the PDP-10 In 1976, Don Woods discovered
Adventure while working at the Stanford Artificial Intelligence Lab, and
obtained Crowther's permission to expand the game. Crowther's original
version was more or less realistic; Woods' changes were reminiscent of
the writings of J.R.R. Tolkien, and included a troll, elves, and a volcano
inspired by Mount Doom. “
Wikipedia, the free encyclopedia
http://en.wikipedia.org/wiki/Interactive_fiction
April 5, 2005
Also know as ADVENT and Colossal Cave
4
Adventure Continues
“My idea was that it would be a computer game that would
not be intimidating to non-computer people, and that was
one of the reasons why I made it so that the player directs
the game with natural language input, instead of more
standardized commands. My kids thought it was a lot of
fun."
— William Crowther
The Colossal Cave Adventure page
http://www.rickadams.org/adventure/a_history.html
April 5, 2005
5
Adventure Examples
Commands
(Adventure) “only accepts commands of one or two words…”
Montfort,2003.
page 108
Examples- “IN”, “N”, “GET SILVER”, “DROP KEYS”, “LAMP ON”,
“XYZZY”, “PLUGH”
Adventure – Solving in in Easy Steps
From The Rom Ranger- Dr. Digital
http://www.textfiles.com/100/adventur.txt
April 5, 2005
Location
“YOU ARE AT A COMPLEX JUNCTION. A LOW HANDS
AND KNEES PASSAGE FROM THE NORTH JOINS A
HIGHER CRAWL FROM THE EAST TO MAKE A
WALKING-PASSAGE GOING WEST. THERE IS ALSO A
LARGE ROOM ABOVE. THE AIR IS DAMP HERE.”
Montfort, Nick 2003
Twisty Little Passages :An Approach to
Interactive Fiction
Cambridge, MA:The MIT Press
page 88
6
ZORK
Zork was developed by students at
MIT’s Laboratory of Computer Science as a follow-up to
Adventure. It was originally written in MDL, a LISP
variant that allowed for the creation of user-defined data
types. The vocabulary of the mainframe version
included 908 words of which 71 were distinct actions.
Leibling, P. David, Marc S. Blank and Timothy A. Anderson 1979
“Zork: A Computerized Fantasy Simulation Game”
IEEE Computer 12(4)(April): 51-59.
http://www.csd.uwo.ca/~pete/Infocom/Articles/ieee.html
April 5, 2005
7
ZORK Object
;"An object: A stack of Zorkmid bills (Zorkmids are the currency of Zork)“
<OBJECT ["BILLS" "STACK" "PILE"]
;"The object's name and synonyms."
["NEAT" "200" "ZORKM"]
;"Adjectives which refer to the object."
"stack of zorkmid bills"
< + ,OVISON, READBIT, TAKEBIT, BURNBIT>
;"Properties of the object: it's visible, readable, takeable,
flammable"
BILLS-OBJECT
( ) ;"The contents of the object (always empty for this object)."
8
ZORK Object (cont)
[ODESC1
"200 neatly stacked zorkmid bills are here."
;"The long description."
ODESCO
"On the floor sit 200 neatly stacked zorkmid bills."
;"The initial long description (when first seen by the player)."
OSIZE 10
;"The object's weight."
OTVAL 15
;"The value of the object: points for finding it and saving it."
OFVAL 10
OREAD ,ZORKMID-FACE
;"What to print when the object is read."]
;"The elements of an object with tokens naming them are rare (few objects
are
readable and thus need OREAD slots). The other slots are common to all
objects.">
9
Zork Object (cont)
;"The object function for the Zorkmid bills. It is there mostly to make a few
sarcastic comments.“
<DEFINE BILLS-OBJECT ( )
<SETG BANK-SOLVE!-FLAG T>
<COND (<VERB? "BURN">
<TELL "Nothing like having money to burn!">
<>) ;"Prints sarcasm but doesn't handle the command
(accomplished by returning the false object <>).
This
allows BURN also to deal with
it."
(<VERB? "EAT">
<TELL "Talk about eating rich foods!">
;"Doesn't allow EAT to run (by returning a non-false.")>>
Leibling, Blank Anderson. 1979
10
“You are Dealing with a Fairly
Stupid Parser”
Montfort.2003
page 107
•
First verifies all words in the command are in its
vocabulary.
Leibling, Blank, Anderson. 1979
•
•
Attempts to reduce the command to a verb and an
optional direct object and indirect object.
Verbs are mapped to known actions. Prepositions are
considered part of the verb for determining an action. For
example “Look under” would be distinct from “Look at”
and handled differently.
Leibling, P. David. 1980
“Zork and the Future of Computerized Fantasy Simulations”
Byte (December)
http://www.csd.uwo.ca/~pete/Infocom/Articles/byte.html
April 10, 2005
11
“Stupid Parser” Continued

The same verb can map to two different
internal action representations.
“Knock down the thief with rusty knife” 
[<action STRIKE> <object THIEF> <object RUSTY-KNIFE>
“Knock on the thief” 
[<action RAP> <object THIEF>
Leibling, Blank, Anderson. 1979
12
“Stupid Parser” Continued


If an object is omitted and only one available object is
associated with the command, the parser will attempt to
use that. For example, if you enter the command
“Attack”, the command attack is associated with a direct
object of type “villain” and an indirect object “weapon”.
If there is only “villain” type object present (for example
“Troll” and you are only carrying one weapon (“sword”),
they are placed in the appropriate spots in the attack
verb frame and the command succeeds without further
action required.
However, if you are carrying two or more weapons, or
nothing that is normally recognized as a weapon, the
interactor will be asked what object to use and the
answer will be rolled in as the object in the command.
Leibling, Blank, Anderson. 1979
13
Parser Continued


Adjectives are used to distinguish between like
objects. For example, the “red button” or the
“blue button” and are otherwise ignored.
They can be combined with “all” and “but” to
specify groups of objects.
Adverbs were considered but not found a good
use for. “The problem is to think of reason
why you would not do everything ‘quietly’,
‘carefully’ or whatever.”
Leibling. 1980
Determiners are completed ignored.

Leibling, Blank, Anderson. 1979
14
ZORK Verb
;"The definition of the `verb' READ:
"<ADD-ACTION "READ"
"Read"
[(,READBIT REACH AOBJS ROBJS TRY)
;"restrictions on characteristics and location of objects for defaulting - filling in an
unadorned
`READ' command. The object must be readable and accessible."
["READ" READER] DRIVER]
;"READER is the function, and the form `READ object' is preferred (the
`driver')"
[(,READBIT REACH AOBJS ROBJS TRY) "WITH" OBJ ["READ" READER]]
;"specification for `READ obj1 WITH obj2'"
[(,READBIT REACH AOBJS ROBJS TRY) "THROU" OBJ ["READ" READER]]
;"specification for `READ obj1 THROUGH obj2'">;“
Synonyms for READ:"<VSYNONYM "READ" "SKIM">;"READER is the general reading
function:“
15
ZORK Verb (cont)
DEFINE READER ( )
<COND (<NOT <LIT?,HERE>> ;"There must be light to read."
<TELL "It is impossible to read in the dark."<)
(<AND <NOT <EMPTY? <PRSI>>>
;"<PRSI> is the indirect object. If there is one, the player is
trying to use something as a
magnifying glass."
<NOT <TRNN <PRSI>,TRANSBIT>> ;"If so, it better be
transparent!">
<TELL "How does one look through a " 1 <ODESC2 <PRSI>> "?">
;"It failed the test, so print sarcasm")
(<NOT <TRNN <PRSO>,READBIT>>
;"The direct object should be readable."
<TELL "How can I read a " 1 <ODESC2 <PRSO>> "?">
;"It's not.")
(<OBJECT-ACTION>
;"Now the object read gets a chance.")
(ELSE ;"It didn't handle it, so print text."
<TELL <OREAD <PRSO>>,LONG-TELL1>)>>
Leibling, Blank, Anderson. 1979
16
Infocom Games
Arthur: The Quest for Excalibur(1989)
Ballyhoo(1986)
Beyond Zork: The Coconut of Quendor (1987)
Border Zone (1987)
Bureaucracy (1987)
Cutthroats (1984)
Deadline (1982)
Enchanter (1983)
Hitchhiker’s Guide to the Galaxy (1984)
Hollywood Hijinx (1986)
Infidel (1983)
James Clavell’s Shogun (1989)
Journey: The Quest Begins (1989)
Leather Goddesses of Phobos (1986)
The Lurking Horror (1987)
A Mind Forever Voyaging (1985)
Moonmist (1986)
Nord and Bert Couldn’t Make Head Or Tail Of It (1987)
Planetfall (1983)
Plundered Hearts (1987)
Seastalker (1984)
Sherlock: The Riddle of the Crown Jewels (1987)
Sorcerer (1984)
Spellbreaker (1985)
Starcross (1982)
Stationfall (1987)
Suspect (1984)
Suspended (1983)
Trinity (1986)
Wishbringer (1985)
Witness (1983)
Zork I (1980)
Zork II (1981)
Zork III (1982)
Zork Zero (1988)
Montfort. 2003
Page 122-124
17
The OZ Project
The OZ Project was a research program out of Carnegie
Mellon dedicated to the development of Interactive Drama.
“We use the phrase ``interactive drama'' to mean the
presentation by computers of rich, highly interactive worlds,
inhabited by dynamic and complex characters, and shaped
by aesthetically pleasing stories….
`highly interactive’ indicates the interactor is choosing what
to do, say, and think at all times…”
Kelso, Margaret Thomas, Peter Weyhrauch and Joseph Bates. 1992
“Dramatic Presenence”
Technical Report CMU-CS-92-195
School of Computer Science
Carnegie Mellon University
Pittsburgh, PA, December
Originally appeared in PRESENCE- The Journal of Teleoperators and
Virtual Environments 2:1
http://www-2.cs.cmu.edu/afs/cs.cmu.edu/project/oz/web/papers/CMU-CS-92.195.pos
Excerpt at http://www-2.cs.cmu.edu/afs/cs.cmu.edu/project/oz/web/overview2.html
April 12, 2005
18
High Level View of OZ
Matteas, Michael. 1997
An Oz-Centric Review of Interactive Drama and Believable Agents
Technical Report CMU-CS-97-156
School of Computer Science
Carnegie Mellon University
Pittsburgh, PA. June
http://www-2.cs.cmu.edu/afs/cs.cmu.edu/project/oz/web/papers/CMU-CS-97-156.html
April 11, 2005
19
Believable Agents


“In an interactive environment, eccentric
personalities … cover up … limitations.”
“(Joseph) Bates (of Oz) recommends modeling …
after … the highly engaging characters of
cartoons, comics, and the theater of the absurd.”
Graceful degradation- “unanswerable questions
are handled in a way that neither halts the
conversation nor break’s the user’s willing
suspension of disbelief.”
Ryan, Marie-Laure. 2001
Narrative as Virtual Reality
Baltimore: The Johns Hopkins University Press
Page 314
20
Believable Agents – other issues



“Incomplete or Ungrammatical Input”
Failure- “Can have personality specific effects…
Misunderstanding is expected.”
Consistency – “It would be difficult to accept as believable
an agent that says things it cannot understand.”
Loyall, A. Bryan. 1997
“Some Requirements and Approaches for Natural Language in a Believable Agent”
Creating Personalities for Synthetic Actors: Towards Autonomous Personality Agents
(Lecture notes in computer science; 1195 : Lecture notes in artificial intelligence)
Robert Trappl; Paola Petta (Eds.)
New York: Springer
Pages 117-118
21
ELIZA Effect

“the tendency for people to treat programs that respond to them (people) as if
they (programs) had more intelligence than they (programs) really do.”
Stern, Andrew. 2002
“Virtual Babyz: Believable agents with Narrative Intelligence”
Narrative Intelligence
Michael Mateas and Phoebe Sengers (Eds.)
Philadelphia: Benjamins Publishing Company
Page 217

“People who knew very well that they were conversing with a machine soon
forgot that fact, just as theater goers, in the grip of suspended disbelief, soon
forget that the action they are witnessing is not ‘real’…. They would often
demand to be permitted to converse with the system in private, and would,
after conversing with it for a time, insist, in spite of my explanations, that the
machine really understood them.”
Weizenbaum, Joseph. 1976
Computer Power and Human Reason
San Francisco: W.H. Freeman and Company
Page 189
22
ELIZA Transcript
“Do you think that I can use the computer this morning?
WHY DO YOU ASK?
I might be able some additional telcomp sales.
WHY AREN’T YOU SURE?
My prospective customers have never seen a demonstration of the system.
DOES THIS MEAN VERY MUCH TO YOU?
Of course it does.
YOU SEEM VERY POSITIVE ABOUT THAT.
This is ridiculous.
WHAT DO YOU MEAN THIS IS RIDICULOUS?
Is there any reason why I can’t use the computer now?
TELL ME MORE ABOUT YOUR PROSPECTIVE CUSTOMERS.
Please dial me up on 491-1850”
Murray, Janet. 1997
Hamlet on the Holodeck: The Future of Narrative in Cyberspace
New York: Free Press
Page 70
As reported by Daniel G. Bobrow of Bolt Beranak and Newman (BBN)
in the December 1968 issue of the SIGART Newsletter
Murray. 1997
page 289
23
Façade: an experiment in interactive drama
“In Façade, you, the player, using your own name and
gender, play the character of a long-time friend of Grace
and Trip, an attractive and materially successful couple in
their early thirties. During an evening get-together at their
apartment that quickly turns ugly, you become entangled
in the high-conflict dissolution of Grace and Trip’s
marriage. No one is safe as the accusations fly, sides are
taken and irreversible decisions are forced to be made.
By the end of this intense one-act play you will have
changed the course of Grace and Trip’s lives – motivating
you to replay the drama to find out how your interaction
could make things turn out differently the next time.”
Matteas, Micheal and Andrew Stern. 2003
Façade: An Experiment in Building a Fully-Realized Interactive Drama
Game Developers Conference, Game Design Track, March
http://www.quvu.net/interactivestory.net/papers/MateasSternGDC03.pdf
April 12, 2005
24
Trip and Grace
Matteas and Stern. 2003
25
Façade - Goals



15-20 minutes of “emotionally intense,
unified, dramatic, action.”
Player should not be just an observer, but
should have a significant effect on events
without obvious branch points (like a Choose
Your Own Adventure or hypertext would
have.)
Should be repeatable 6-7 times without
player necessarily feeling s/he has exhausted
all the possibilities
Matteas and Stern. 2003
26
Façade



Player interacts through movement and some gestures
using the mouse and through typing in spoken dialog.
Characters respond with spoken dialog and actions.
Drama manager controls story beats. Changed about
once a minute.
Players actions are interpreted as “discourse acts”, “a
concise summary of the general meaning”. These
discourse acts are interpreted differently depending on
the beat and effect the choice of future beats.
Matteas and Stern. 2003
27
Discourse Acts
Most have an option to refer to a character.
“agree
referTo <topic>
disagree
praise
positive exclamation
ally
negative exclamation
criticize light
express happy
criticize harsh
express laugh
oppose
express sad
flirt
express angry
pacify
maybeUnsure
provoke
dontUnderstand
greet
thank
goodbye
apologizeExcuseMe
getAttention
intimate
judgment
suggestionAdvice
misc-custom
destructiveManipulation
jokeTestLimits
inappropriate
bug
comfort
kiss
physicallyFavor
wanderAway”
Matteas and Stern 2002
Page 15
Unrecognizable text maps to a discourse act “systemDoesNotUnderstand”
Matteas and Stern 2002
Page 16
28
Façade – Natural Language Understanding



Understanding is Broad and Shallow. Not
concerned with syntax or semantics, but with the
pragmatic effects.
Phase 1 turns surface text into discourse acts.
Phase 1 rules are generally shared across all
beats. Rules map “islands” of text.
Phase 2 determines what effect the discourse act
has on behavior of the characters
Mateas, Michael and Andrew Stern. 2004
“Natural Language Understanding in Façade: Surface Text Processing”
Best Paper Award, Technologies for Interactive Digital Storytelling and
Entertainment (TIDSE),, Darmstadt, Germany, June
Page 2
http://www.quvu.net/interactivestory.net/papers/MateasSternTIDSE04.
pdf
April 11, 2005
29
Pattern Sub-language
(X Y)
(X | Y)
([X])
*
?
(tand X Y)
(tor X Y)
(toc X)
(tnot X)
exactly X and Y
exactly X or Y
optional
Many words
One word
X and Y in the string in any order
X or Y in the string
X in the string
X not in the string
Basically regular expressions with some shortcuts to allow easy typing.
Mateas and Stern. 2004
Page 5
30
Template Language
;; A template rule for agreement
(defrule global-agree-rule1
(template (toc (love (to | it | that))))
=>
(assert (iAgree)))
iAgree will combine with other rules to determine
addressed (potentially none) to produce DAAgree
Mateas and Stern. 2004
Page 5
31
Positional Facts
Rules can provide positional information about where the match occurs.
;;Rule for recognitional positional “is” fact
(defrule positional_Is
(template (tor am are is seem seems sound sounds look looks))
=>
(assert (iIs ?startpos ?endpos)))
;;Rule for recognizing positional “positive description fact
(defrule positional_PersonalPosDesc
(template (tor buddy comrade confidant friend genius go-getter pal sweetheart))
=>
(assert (iPersonalPosDesc ?startpos ?endpos))
;; Rule for recognizing praise
(defrule Praise_you_are_PersonPOs
(template ({iPersonPosDesc} | (you [{iIs}] [a|my] {iPersonPosDesc} *)))
=>
Mateas and Stern. 2004
(assert (iPraise)))
Page 7
32
Sample Rules
Processing “Hello, Grace”
Pseudocode:
“hello”  iGreet
“grace”  iCharacter(Grace)
iGreet and iCharacter(?x)  DAGreet(?x)
means DAGreet(Grace) Mateas and Stern. 2004
Page 2
Additional iGreet rules would be written for other greetings
than hello.
Mateas and Stern. 2004
Page 3
33
Rules Additional


Rules can be specified to use WORDNET for
synonym and hyponym relationships. For
example, a rule could apply to “alcoholic
beverage” and if you said “I’d like some Chablis”,
the parser would determine that “Chablis” is a
kind of wine which is a kind of alcoholic beverage
and that rule potentially applies.
Rules can also support stemming.
Mateas, Michael and Andrew Stern. 2002
“Architecture, Authorial Idioms and Early Observations of the Interactive Drama Façade “
CMU-CS-02-198
December 5, 2002
http://reports-archive.adm.cs.cmu.edu/anon/2002/CMU-CS-02-198.pdf
Page 16
34
April 11, 2005
Rule Ranking
•
•
•
•
First tier of rules handle low-level patterns (like is
rule)
Second tier handles idiomatic expressions
(~1000 pertinent to the domain)
Third tier handles negation
Final tier looks for key words and combinations
(like in positional example) to produce final
discourse act.
Mateas and Stern. 2004
Page 9
35
Rules

~800 template rules compile to ~6800 internal
rules
Mateas and Stern. 2004
Page 7

Rules “err on the side of being overly permissive.”
Statements made by players may be
misinterpreted and the characters aren’t going to
be correcting anyone’s grammar.
Matteas and Stern 2002
Page 28
36
Discourse Act Examples
(DAAgree ?char)
(DADisagree ?char)
(DAPositiveExcl ?char)
(DANegExcl ?char)
(DAExpress ?char ?type)
Certainly. No doubt. I would love to.
No way. Fat chance. Get real. Not by a long shot.
Yeah. Wow. Breath of fresh air.
Damn. That really sucks. How awful. D’oh.
I’m thrilled.  That bums me out. 
ha ha (laughter) It really pisses me off (angry)
(DAMaybeUnsure ?char) I don’t know. Maybe. I guess so. You’ve lost me.
(DaThank ?char)
Thanks a lot
(DaGreet ?char)
Hello. What’s up.
(DAAlly ?char)
I like you. You are my friend. I’m here for you.
(DAOppose ?char)
Kiss off. You’re the worst. I hate you.
(DADontUnderstand ?char)I’m confused. I don’t get it. What are you talking
about.
Mateas and Stern. 2004
Page 3
37
Discourse Act Examples (cont)
(DAApologize ?char)
I’m sorry. My bad. How can I make this up to you.
(DAPraise ?char)
You’re a genius. What a sweetheart you are.
(DACriticize ?char ?level) You’re weird. (light) What a dipshit. (harsh)
(DAFlirt ?char)
You look gorgeous. Kiss me.
(DAPacify ?char)
Calm down. Relax, guys. Take it easy.
(DAExplain ?param ?char) Grace is lying. Trip is having an affair.
(DAAdvice ?param ?char) You should get a divorce. Try to work it out.
(DAReferTo ?char ?obj)
I like the couch. Your wedding picture looks nice.
(DAIntimate ?char)
What’s wrong? Let it all out. Talk to me.
(DAGoodbye ?char)
Catch you later. So long. I’m out of here.
(DAInappapriate ?char)
“slut”
(DAMisc ?char ?type)
I’d like a drink. Is this a bad time. Should I leave.
Mateas and Stern. 2004
Page 4
38
Phase 2




Reaction rules map discourse acts to reaction.
Unlike the phase 1 rules, the templates for
reaction rules are beat-specific.
There also some shared global context.
Each beat maps some or all ~40 discourse acts
to 5-10 local reactions.
Matteas and Stern 2002
Page 16-17
39
Typical Reactions
Local
“Player is mildly agreeing with the question/situation posed to her in this beat.
Player is strongly agreeing with the question/situation posed to her in this beat.
Player is mildly disagreeing with the question/situation posed to her in this beat.
Player is strongly disagreeing with the question/situation posed to her in this beat.
Player is not giving a direct answer to the question/situation posed to her in this beat.”
Global - hundreds
“Player has referred to an object in the room
Player has done an affinitity move (e.g. praise, criticize, flirt)
Player has referred to a related topic (e.g. marriage, divorce, infidelity)
Player had repetitively pushed on a topic.
Player has referred to the content of a previous beat.”
If no reaction applies, system must deflect.
Matteas and Stern 2002
Page 16-17
40
Beats






Each Beat has “goals” and a “gist”. The gist generally
occurs when all beat goals have been met.
Before a gist occurs, reactions are consider “mixins”,
causing the characters to react but not resolving the beat.
After a beat gist occurs, one reaction will be a “transitionout.” There is one transition-out per beat.
Mixins and transitions-out may have effect global state.
To handle interrupts, beat goals have “repeat dialog
alternatives” and “reestablish” dialog.
“Drama manager” aka “beat sequencer” chooses next
beat based on rules and interactions.
Matteas and Stern 2002
Page 17-19
41
Trip and Grace
Matteas and Stern. 2003
42
INFORM
INFORM is one of the languages most commonly
used by Text Adventure hobbyists today. It
produces code that runs on the same virtual “ZMachine” that was used to run ZORK and
various other Infocom games when they were
released commercially.
Nelson, Graham. 2001
The Inform Designers Manual
Fourth Edition
St Charles, IL: The Interactive Fiction Library
http://www.inform-fiction.org/manual/DM4.pdf
April 10, 2005
Page I
43
Inform Parser Grammar
COMMAND  <oops-word><word> | <action phrase> | <order>
<oops-word>  “oops” | “o”
<order>  <actor> “,” <action phrase>
<actor>  <noun phrase>
<action phrase>  <verb phrase> | <verb phrase> <then-word> <action phrase>
<then-word>  “.” | “then”
<verb phrase>  <again-word> | <imperative verb> <grammar line>
<again-word>  “again” | “g”
<grammar line>  <noun phrase > | <preposition> <noun phrase> |
<grammar line>  <noun phrase> <preposition> <noun phrase> | …
<preposition>  “on” | “under” …
<noun phrase>  <basic np> | <basic np> <connective> <noun phrase>|…
<connective>  <and-word> | <conjuction> | <but-word> <disjunction>
<and-word>  “,” | “and”
<but-word>  “but”| “except”
Nelson. 2001
pages 245-246, 250
44
Inform Parse
Parse of sentence “conan, put every sword in the box”
Nelson. 2001
pages 250
45
Links and Resources







Interactive Fiction Archive- http://www.ifarchive.org
ZORK- http://www.infocom-if.org/downloads/downloads.html
Hitchhiker’s Guide to the Galaxyhttp://www.bbc.co.uk/radio4/hitchhikers/game.shtml
Hamlet- The Text Adventurehttp://www.robinjohnson.f9.co.uk/adventure/hamlet.html
Façade (coming soon, hopefully)http://www.quvu.net/interactivestory.net
Group Blog- http://www.grandtextauto.org
Rec.arts.int-fiction and Rec.games.int-fiction
46
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