For me it's either Techno music, Dubstep, Metal, or Rock.
Recently my playlist was this:
War Pigs - Black Sabbath
Jordan - Buckethead
Ghosts N Stuff - Deadmau5
Moar Ghosts N Stuff - Deadmau5
2011 Dubstep Mix - Various artists
Escape the Fate - all songs I have by them
and a bunch of other songs mostly the genres I listed above.

So what music do you listen to (if any) while you game?