But Half Life and Portal are master pieces though. Even though I love WoW, developing a game like HL would be more fun. Doesn't even have to be any of those games, just similar games like that with interesting game play.
BioWare would be awesome as well. Dragon Age and Mass Effect? Yes please.
But, I'd prefer working on a FPS game with fun/interesting gameplay, like HL/Portal/Thief.