It has :
CoD4, Mw3, Counter Strike, Counter Strike : Condition Zero, Counter Strike : Source and Beta, Day of Defeat, Day of Defeat Source, Deathmatch Classic, Driver San Francisco, Garry Mod, Gotham City Imposters, GTA, GTA2,GTA3,GTA III, GTA IV, GTA : Episode from Liberty City, GTA : San Andreas, GTA : Vice City, GTA 3: Scan Andreas Mac, GTA3 Vice City MAC, Half Life, Half Life 2, Half Life 2 : Deathmatch, Half Life 2 : Episode 1, Half Life 2 : Episode 2, Half Life 2 : Lost Coast, Half Life 2 : Deathmatch : Source, Half Life : Blue Shift, Half Life : Opposing Force, Half Life : Source, Left 4 Dead, Left 4 Dead 2, PAYDAY : THE HEIST, PORTAL, PORTAL 2, RICOCHET, TEAM Fortress 2, Team Fortress 2 Beta, Team Fortress Classic, and Vessel.
How much? Ah that was a lot of typing