all for pc:
Starcraft ; Broodwars expansion
Age of Empires 2 ; Conquerors expansion
Diablo II ; Lord of Destruction expansion
Black & White
I'm also hoping to get in the near future:
B&W expansion
Aliens Vs. Predators 1 and/or 2 (most likely just 2)
World of Warcraft (when it comes out... hopefully some time soon =/) (not Warcraft 3 mind you
)