I like making (modifying) models for the HL2 source engine, which is what I spend most of my time doing.
I like to play multiplayer games on steam, some of the games I play:
Call of Duty: World at War (Zombies)
Call of Duty: Black Ops
Obsidian Conflict (HL2 mod)
Garrysmod (to make gmod poses, or test models)