I listen to gaming music when playing games. So the Hell Marches, mostly the second one. Halo music, mostly Mjolbir Mix, Reclaimer, the Banshee theme and One final effort. The music from Sonic and some OCremixes like Wanderer on the offensive, Mud Mix (Slower paced games only) and Red Scare.
I only listen to music when I'm in Forge by myself with no one else talking to me. I find music distracting when I'm actually playing a game though I do somewhat better in CoD 4 with some rock music on. I listen to things like Disturbed, Linkin Park, A7X, Kanye West, T.I. ...mostly hip-hop and rock.
Remember - post what you listen to first, then your response/reaction to what other people have put. Or the other way around.
I listen to a wide variety of music while I game Eminem Guns N' Roses Linkin park. Barenaked Ladies Modest Mouse The Game (only How we Do) Black Eyed Peas Gorillaz Bob Marley
I only listen to music normally during Customs or Forging. When Forging I try to listen to calming music so I don't literally throw my controller at my wall for becoming so frustrated with Forging. While in Customs I try to listen to Metal to get me pumped up like Mastodon, Disturbed, Megadeth, In Flames or Protest the Hero. Although, I sometimes do listen to music while playing matchmaking if I'm not taking it seriously (during Big Team or Squad Battle, mostly)