1701 AD
AirMech (is this still in Alpha?)
Alan Wake & American Nightmare
Alice: Madness returns
Alien Shooter
Alien Shooter 2 - Reloaded
Aliens versus Predator Classic 2000
Anomaly Warzone Earth
Amnesia
And Yet It Moves
Aquaria
Arx Fatalis
Assassins Creed 1 & 2
Atari: 80 Classic Games in One! (Removed from Steam ages ago)
Audiosurf
Auditorium
Avadon: The Black Fortress
Avencast: Rise of the mage
Avernum 4-6
Babo - Invasion (do not run, behaves strange and stays active process)
Bards Tale 2004
Beat Hazard
Beyond Good & Evil
bit.trip beat
bit.trip runner
Blade Kitten
Blue Berry Garden
Borderlands
Braid
Brainpipe
Brink
Broken Sword 3 : Sleeping Dragon
Brothers in Arms : Earned in Blood
Brothers in Arms Road to Hill 30
Bully
Bunch of Heroes
Burn zombie burn
Burnout Paradise the Ultimate Box
C&C 3, 4 RA3 & Kanes Wrath
Call of Cthulhu
Capsized
Caster
Cave Story+
Ceville
Chains
Chime
Chrome
CivCity Rome
Civilization IV, Colonization*
Commandos – all games
Cossacks: European Wars
Costume Quest
Crazy Taxi
CreaVures
Critical Mass
Crysis
Crysis Warhead
Dark Messiah of Might and Magic
Darksiders II
Darkstar One
Darwinia
Deadly Premonition Director's Cut
Dead Space 1&2
Dear Esther
Deathspank – all games (Thongs of Virtue, Baconing & Deathspank)
Defence grid
Delve deeper
Depths of Peril
Deus Ex GOTY
Deus Ex Human Revolution & Missing Link DLC
Deus Ex: Invisible War
Diamond Dan
Din's Curse
Disciples 2 Gold
Divinity 2 : Dragon Knight Saga
Divinity Original Sin beta
Doc Clock - The Toasted Sandwich of Time
Doom 3 & ROE Expansion
Dragon Age Ultimate Edition
Dreamfall: The Longest Journey
Duke Nukem Forever
Dungeon Siege 1&3
Dustforce
Dwarfs!?
E.y.e.: Divine Supremacy
Edge
Eets
Elder Scrolls Oblivion
Empire: Total War
Eschalon: Book 1
Eschalon: Book 2
Europa Universalis III - Complete
Eversion
Everyday Genius: SquareLogic (No longer on Steam. Should hopefully return, though.)
Fallout New Vegas
Fantasy Wars
Far Cry*
Fate of the world
Fear 1&2
FEAR 2
Floras Fruit Farm
Fortix
Fortix 2
Freedom Force
Freedom Force vs the 3rd Reich
Front Mission Evolved
FTL: Faster Than Light
Future Wars
Galactic Civilizations I Ultimate Edition
Geneforge I-V
Geometry Wars: Retro Evolved
Ghost Recon Advanced Warfighter
Ghost Recon Advanced Warfighter 2
Gish
Gothic
Gothic II
Gothic series (I, II, III, Forsaken Gods and ArcaniA)
Grand Theft Auto 3
Gravitron 2
Greed Corp
Greed: Black Border
Grid
Grotesque tactics
GTA Vice City
GTA: San Andreas
Gaucamelee! Gold Edition
Gundeadligne
Gundemonium recollection
Gyromancer
Half-life 2 (+ep 1&2)
Half-Life games, all of them (surprise)
Hamilton's great adventure
Hammerfight
Hard Reset
Hero Academy
Hitman 2 & Blood Money
Hitogata Happa
Hydrophobia
Indiana Jones and the Fate of Atlantis
Indiana Jones and the Last Crusade
Infernal
ion assault
Jade Empire
Jagged Alliance 2 Gold
Jagged Alliance 2 Gold Unfinished Business
Jedi Knight (and Mysteries of the Sith), Jedi Outcast, Jedi Academy
Jolly Rover
Just Cause 2
Kaptain Brawe
King Arthur - The Role-playing Wargame
King's Bounty - The Legend
King's Bounty Armored Princess
King's Bounty Crossworlds
Knights of Honor
Koahn II
Kohan Ahrimans Gift
Kohan Immortal Sovereigns
KOTOR
Kung Fu Strike: The Warrior's Rise
La-Mulana
Lara Croft and the guardian of light
Limbo
Loom
Mafia
Magic the Gathering 2012
Magicka
Mass Effect 1+2*
Max and the magic marker
Max Payne 1 & 2
Medieval II Total War
Metro 2033*
Mirror's edge*
Monkey Island 2
Morrowind
Mount&Blade
Mount&Blade: Warband*
Mr. Robot
Napoleon Total War
Necrovision
Neverwinter Nights 2*
New Star Soccer 5
Nexuiz
Nexus The Jupiter Incident
NightSky
Nikopol: Secrets of the Immortals
Obulis
Oddworld: Abes Exoddus
Oddworld: Abes Oddysee
Orcs Must Die!
Osmos
Painkiller Black Edition
Painkiller Overdose
Painkiller Resurrection
Penumbra (all of it)
PixelJunk Shooter
Plants vs zombies
Poker Night at the Inventory
Port Royale 2
Portal 2
Post Apocalyptic Mayhem
Prince of Persia (2008) - launcher runs, game does not
Prince of Persia Two Thrones & Warrior Within
Project Snowblind
Prototype 2
Puzzle Agent
Puzzle Agent 2
RAGE
Railroad Tycoon 2: Platinum
Rainbow Six 3 Gold
Rainbow SIx Lockdown
Rainbow Six Vegas
Rainbow Six Vegas 2
Recettear
Red Faction Armageddon
Red Faction: Guerrilla
Renegade Ops
Return to Castle Wolfenstein
Rip Trilogy
Risen
Roboblitz
Rogue Trooper
Rochard
Rome Total War Alexander
Rome Total War Gold
Rune Classic
Runespell: Overture
rush
Sacred Gold
Saints Row 2*
Saints Row the Third
Sam & Max (all of them)
Sanctum
Scorgasm
Sequence
Serious Sam HD first and second encounter
Shank
Shatter
Shdowgrounds + S: Survivor
Sid Meier's Civilization III, but not the editors
Sid Meiers Civilization V
Sid Meiers Pirates
Sideways: New York
Sin 1 & 2
Skyrim
Sleeping Dogs
Sonic CD
sonic generations
Space Empires IV Deluxe
Space Giraffe
Space pirates and zombies
Spacechem
Spec Ops: The Line*
Spellforce 2 Gold Edition
Spellforce Platinum Edition
Splinter Cell
Splinter Cell - Double Agent
Splinter Cell Chaos Theory
Stacking
Stalker Clear Sky*
Stalker CoP & SoC
Star Wolves
Starscape
Sword and Sworcery
Sword of the Stars Complete Collection
Swords and Soldiers
Syberia
Syberia 2
Tales of Monkey Island Chapter 2 - 5
Terraria
The Baconing
The Ball
The Dig
The Guild 2: Rennaisance*
The Last Remnant
The Longest Journey
The Maw
The Secret of Monkey Island Special Edition
The Ship
The Void
The Void
The Witcher*
Thief : Dark Shadows
Titan Attacks
Titan Quest (+ IT)
Toki Tori
Tomb Raider: Anniversary
Tomb Raider: Legend
Tomb Raider: Underworld
Torchlight (but TorchEd works fine without Steam)
Torchlight 2
Total War Shogun 2
Trine
Trine 2
Tropico
Tropico 2
Tropico 3
Tropico 4
Twin Sector
Two Worlds II
Universe Sandbox
Uplink
Vampires the masquerade: Bloodlines
Velvet Assassin
Vessel
Warhammer 40k Dawn of War and Dawn of War 2 and all DLC / Expansions
Warlock: Master of the Arcane
Wasteland Angel*
Wolfenstein & RTCW
World of Goo
Worms Blast
X - Beyond the Frontier
X - Tension
X2 - The Threat
X3 - Albean Prelude
X3 - Reunion
X3 - Terran Conflict
X-COM: Interceptor and Enforcer
Xotic
Yosumin
Your doodles are bugged!
Zeno Clash
Zombie Driver
Zombie shooter 1+2