0-9
T2300    - 2300 AD/Traveller 2300
7Sea     - 7th Sea
Swash    - 7th Sea d20/Swashbuckling Adventures

A
AGoT     - A Game of Thrones
ASoIF    - A Song of Ice and Fire
A-St     - A-State
Abrnt    - Aberrant (original)
Abr20    - Aberrant d20
ADnD_    - AD&D (insert edition number)
Advn     - Adventure (original)
Adv20    - Adventure d20
Amath    - Aftermath
AFMBE    - All Flesh Must Be Eaten
Alt+     - Alternity
AmGO     - Amber - Guardians of Order
ADRPG    - Amber Diceless Roleplaying - Phage Press
Anima    - Anima RPG
ApocW    - Apocalypse World
Arma     - Armageddon
AofD     - Army of Darkness
Arwf     - Arrowflight
AM++     - Ars Magica
ATSA     - Atlantis: The Second Age
AtomH    - Atomic Highway
SASA     - Authority

B
Bab20    - Babylon 5, d20 rules.
BabP     - Babylon Project
BFRPG    - Basic Fantasy RPG
BRP+     - Basic Roleplaying
BWBH     - Bat-Winged Bimbos from Hell
BSG+     - Battlestar Galactica
BtSv_    - Beyond the Supernatural  (insert version number)
BBSW     - Big Breasts, Small Waist (hentai version of BESM)
BESM     - Big Eyes, Small Mouth
BESM20   - Big Eyes, Small Mouth, d20
BFG+     - Battlefleet Gothic
BB++     - Blood Bowl
BlPl     - Blue Planet
Boot     - Boot Hill
BNW+     - Brave New World
BEER     - Brawn, Ego, Extraneous, and Reflexes: Kobolds Ate My Baby (aka KAMB)
BrGr     - Broken Gears
BtVS     - Buffy the Vampire Slayer
BnB+     - Bunnies and Burrows
BGC+     - Bubblegum Crisis
Burn     - Burning Wheel
Bush     - Bushido

C
CoC100   - Call of Cthulhu d100 rules
CoC20    - Call of Cthulhu d20 rules
CoC5.5   - Call of Cthulhu version 5.5
C3:16    - Carnage 3:16
CAH+     - Cartoon Action Hour
CF-G     - GURPS Castle Falkenstein
CF-T     - Castle Falkenstein (original Talisorian version)
CnC+     - Castles and Crusades
Champ    - Champions
CtD_     - Changeling: the Dreaming (insert edition number)
CtL+     - Changeling: the Lost
CnS+     - Chivalry and Sorcery
CJCW     - CJ Carella's WitchCraft
TravC    - Classic Traveller (the Little Black Books)
ColG     - Colonial Gothic
Con+     - Conan
ConX     - Conspiracy X
CRiTY    - Continuum: Roleplaying in The Yet
Corp     - Corporation
CORPS    - BTRC CORPS RPG
CSRPG    - Cortex System RPG
Crim     - Crimson Skies
Ctech    - Cthulhutech
CGen     - Cybergeneration
CPnk     - Cyberpunk
CPnk20   - Cyberpunk 2020
Cpnk3X   - Cyberpunk 203X

D
D20M     - d20 Modern
DA-F     - Dark Ages: Fae
DA-I     - Dark Ages: Inquisitor
DA-M     - Dark Ages: Mage
DA-V     - Dark Ages: Vampire
DA-W     - Dark Ages: Werewolf
DCon     - Dark Conspiracy
DkFt     - Dark Future
DHer     - Dark Heresy
Dar_     - Darwin's World (_ indicates edition number)
DCH+     - DC Heroes
DCU+     - DC Universe
Dead     - Deadlands
DNW+     - Deeds Not Words
DtF_     - Demon: the Fallen (Insert edition number)
DB++     - Digital Burn
DWATS    - Doctor Who: Adventures in Time and Space
DWRPG    - Doctor Who RPG (FASA/GW)
DitV     - Dogs in the Vineyard
DW++     - Dragon Warriors
DBZ+     - Dragonball Z
DQ++     - DragonQuest
DR++     - Dragonroar
DochD    - Drakar och Demoner
DrmPk    - Dream Park
DFRPG    - Dresden Files RPG
Dune     - Dune: Chronicles of the Imperium
DCCRPG   - Dungeon Crawl Classics RPG
DnD3._   - D&D 3.0 or 3.5
DnD4e    - D&D 4th edition
DnDAU    - D&D Arcana Unearthed variant
DnD+     - D&D (Basic, Expert, etc...)
DE++     - Dying Earth

E
ED++     - EarthDawn
Eber     - Eberron
EclPh    - Eclipse Phase
EPT+     - Empire of the Petal Throne
EABA     - End All Be All
EHrt     - Engine Heart
Ethr     - Etherscope
EQ++     - EverQuest
Exal     - Exalted

F
FS++     - Fading Suns
Fall     - Fallout
FanC     - Fantasy Craft
FATE     - FATE: Fantastic Adventures in Tabletop Entertainment.
FT++     - The Fantasy Trip
FwtD     - Fates Worse Than Death
Fear     - Fear Itself
Feng     - Feng Shui
Fiasco   - Fiasco
Fief     - Fief
FFRPG    - Final Fantasy RPG
Fire     - Fireborn
Free     - Free-form (only a suggestion)
FUDGE    - Fudge
Fuz_     - Fuzion, (insert edition number).

G
GW++     - Gamma World
GW20     - Gamma World d20 rules
GW-DnD   - Gamma World (4e D&D conversion)
Gang     - Gangbusters
GtSE     - Geist: the Sin Eaters
GORE     - Generic Old-school Role-playing Engine
GURPS_   - GURPS, (insert edition number)
CF-G     - GURPS - Castle Falkenstein
Trav-G   - GURPS - Traveller
GBI+     - GhostBusters
GnG+     - Ghouls and Ghosts
GH++     - Golden Heroes
Grimm    - Grimm RPG

H
Hack     - HackMaster
HCoV     - Haven - City of Violence
HvG      - Heavy Gear
HW++     - Hero Wars
Heroes   - Heroes System
HU++     - Heroes Unlimited
HU2d     - Heroes Unlimited 2nd Edition
HU2dR    - Heroes Unlimited 2nd Edition (Revised)
HQ++     - Heroquest
HEX+     - Hollow Earth Expedition
Home     - "Home-brewed" rules (ie: not commercially avalable, and not free-form)
HoL+     - Human Occupied Landfill
HtR_     - Hunter: the Reckoning (insert edition number)
HtV      - Hunter: the Vigil

I
Imm+     - Immortal - Invisible War
IN++     - In Nominé
Inqu     - Inquisitor
InSp     - InSpectres
IC++     - Ironclaw

J
JC++     - Jadeclaw
JD++     - Judge Dredd
JD20     - Judge Dredd d20
Just     - Justifiers

K
KAMB     - Kobolds Ate My Baby
KotE     - Kindred of the East

L
LabL     - Labyrinth Lord
Lace     - Lace and Steel
Lady     - Lady Blackbird
LnL+     - Legends & Labyrinths
L5R_     - Legend of the Five Rings (insert edition number)
LoA+     - Legends of Anglerre
LFNE     - Little Fears: Nightmare Edition
LiSt     - Living Steel
LW++     - Lone Wolf RPG
LotR     - Lord of the Rings

M
MWWG     - Macho Women with Guns
M-SC     - Mage: Sorcerer's Crusade
MtA_     - Mage: the Ascension (insert edition number)
MtAw     - Mage: the Awakening
Maid     - Maid RPG
MMnM     - Man, Myth and Magic
Trav4    - Mark Miller's Traveller (aka Traveller 4)
MSH+     - Marvel Super Heroes
MSHS     - Marvel Super Heroes - SAGA
MU++     - Marvel Universe
M+M      - Mazes and Minotaurs
Mech     - Mech Warrior
MechD    - Mechanical Dream
MTrav    - Megatraveller
MSPI     - Mercenaries, Spies, & Private Eyes
Alpha    - Metamorphosis Alpha
M20      - Microlite 20
MERP     - Middle Earth Roleplaying
MongT    - Mongoose Traveller
Mord     - Mordheim
MP++     - Morrow Project
MGrd     - Mouse Guard
MtR_     - Mummy: The Resurrection (insert edition number)
Mkin     - Munchkin
Mtnt     - Mutant
MnM_     - Mutants and Masterminds (insert edition number)

N
Necro    - Necromunda
nWoD     - New World of Darkness
NLife    - Night Life
NaSSv_   - Ninjas and Super Spies  (insert version number)
Nobil    - Nobilis

O
ORPG     - Ork RPG
Orph     - Orpheus
OSuns    - Other Suns
OtE+     - Over The Edge

P
Pall     - Palladium RPG
Para     - Paranoia
PaXP     - Paranoia XP
Pass     - Passages
Path     - Pathfinder
Pend     - Pendragon
Pkth     - Pokethulhu
PnP+     - Powers and Perils
PD1+     - Prime Directive 1st Edition
PD-G     - GURPS Prime Directive
PDd20    - Prime Directive d20
PDd6     - Prime Directive d6
Priv     - Privateers and Gentlemen
PtC_     - Promethean: the Created

Q
QAGS     - Quick Ass Game System

R
RedD     - Red Dwarf
RNoW     - Renegade Nuns on Wheels
Rifts    - Rifts
RISUS    - RISUS
Robo     - Robotech
=RT=     - Rogue Trader
Role     - Rolemaster
RQv_     - Runequest (v_ is version number)
MRQ+     - Runequest (Mongoose press)

S
SavW     - Savage Worlds
S:H+     - Scion: Hero
S:D+     - Scion: Demigod
S:G+     - Scion: God
SZir     - Secrets of Zir'an
Ser+     - Serenity RPG
SRv_     - ShadowRun (v_ is the version number
SAS+     - Silver Age Sentinels
SLA+     - SLA Industries
Sorc     - Sorcerer
1889     - Space 1889
SO++     - Space Opera
Space    - Spacemaster
Splc     - Splicers
SC20     - Spycraft d20 rules
SF++     - Star Frontiers
ST-DC    - Star Trek - Decypher
ST-FASA  - Star Trek - FASA/Games Workshop
ST-LU    - Star Trek - Last Unicorn
SWd6_    - Star Wars (West End Games) (insert edition number)
SWd20    - Star Wars d20 rules
SWSE     - Star Wars Saga Edition
Strb     - Starblazer
SG-1     - Stargate
SsTr     - Starship Troopers
SPQR     - Steve Perrin's Quest Rules
STOCL    - STOCS Lite
STOCS    - STOCS RPG
SFtSG    - Street Fighter: the Storytelling Game
Supe     - Supernatural RPG
Swash    - 7th Sea d20/Swashbuckling Adventures
S7S+     - Swashbucklers of the Seven Skies
SnW+     - Swords and Wizardry

T
TfFV     - Tales from the Floating Vagabond
Talis    - Talislanta
TMNT     - Teenage Mutant Ninja Turtles and Other Strangeness
TfOS     - Teenagers from Outer Space
TerP     - Terra Primate
TAIJ     - The Adventures of Indiana Jones
FT++     - The Fantasy Trip
TOR+     - The One Ring
TRoS     - The Riddle of Steel
TSoY     - The Shadow of Yesterday
TINS     - There Is No Spoon
Toon     - Toon
TORG     - Torg
ToCt     - Trail of Cthulhu
Tran     - Transformers
Trav-G   - GURPS Traveller
Trav4    - Mark Miller's Traveller (aka Traveller 4)
Trav5    - Traveller 5
T2300    - Traveller 2300/2300 AD
Td20     - Traveller d20
TravC    - Classic Traveller (the Little Black Books)
TNE+     - Traveller: The New Era
Trin     - Trinity
TSdx     - TriStat dx
True20   - True 20 (Blue Rose, etc)
TnT+     - Tunnels and Trolls
T2K+     - Twilight 2000
T2k13    - Twilight 2013

U
Ubiq     - Ubiquity
Under    - Underground
UnhM     - Unhallowed Metropolis
UnkA     - Unknown Armies
UniS     - UniSystem

V
VtDA     - Vampire: The Dark Ages
VtM_     - Vampire: the Masquerade (insert edition number)
VtR+     - Vampire: The Requiem
VicV     - Victorian Age Vampire
VnV+     - Villains and Vigilantes
Void     - Void Trek 3007 AD

W
WH40K    - WarHammer 40K
WHFB     - WarHammer Fantasy Battle
WFRP     - Warhammer Fantasy Roleplaying
WarM     - Warmaster
WstW     - WasteWorld
WotG     - Weapons of the Gods
WtA_     - Werewolf: the Apocalypse (insert edition number)
WtF+     - Werewolf: the Forsaken
SWWE     - West End Games Star Wars
WoT+     - Wheel of Time
Wind     - The Window
CJCW     - CJ Carella's WitchCraft
OWoD_    - World of Darkness (_ edition number)
WoW+     - World of Warcraft RPG
WBey     - Worlds Beyond
WtO_     - Wraith: the Oblivion (insert edition number)
Wushu    - Wushu

X
XCra     - XCrawl
Xeno     - Xenoforce
XroD     - Xro Dinn Chronicles

Y
YotP     - Year of the Pheonix

Z