From memory
Warcraft 3: Reign of Chaos
Warcraft 3: The Frozen Throne
Wanted: Weapons of Fate
Tomb Raider: Anniversary
Age of Empires 2
Age of Empires 3
Empire Total War
Splinter Cell Chaos Theory
Warhammer Online Age of Reckoning
World of Warcraft
Aion
Star Wars: Dark Forces II
Starwars: The Jedi Outcast
Rainbow Six
World In Conflict
Diablo 2
Diablo 2: Lord of Destruction
Battlefield 2142
Deadspace
Call of Duty: Modern Warfare
Call of Duty: Modern Warfare 2
Mech Warrior 4: Vengence
Mech Commander 1
Ghost Reacon Advanced Warfighter
Heroes of Newerth
Assassin's Creed
Elder Scrolls III: Morrowind
Elder Scrolls III: Tribunal
Elder Scrolls III: Bloodmoon
Elder Scrolls IV: Oblivion
Audiosurf
Beat Hazard
Counterstrike: Source
Portal
Half-life
Half-life 2
Half-life 2 Episode 1
Half-life 2 Episode 2
Day of Defeat: Source
Gary's Mod
Mount and Blade: Warbands
Warhammer 40k: Dawn of War 2
Warhammer 40k: Dawn of War 2 Chaos Rising
Mass Effect 1
Mass Effect 2
Alien Versus Predator
Half-life 2: Team Deathmatch
Left 4 Dead
Mass Effect
Mass Effect 2
The Path
Saints Row 2
Team Fortress 2
Dragon Age: Origins
Stalker: Shadow of Chernobyl
Harry Potter and the Philosopher's Stone
Harry Potter and the Chamber of Secrets
Far Cry
I've probably forgotten some xD
These are all owned legally, the list would be waay longer otherwise
If I get to count my sister's games (I get to play hers she gets to play mine
) I could add more
( she owns all the sims games
)