Kickass Video Game Soundtrack Suggestions

I am in the process of making a Machinima with Garry’s Mod (durrrr) and I was wondering what cool video game soundtracks would be good for a action shooter film? Any suggestions would be awesome! And I would prefer if they could be bought on iTunes. I don’t pirate, it’s dirty :slight_smile:

Don’t ask Facepunch for help with this stuff. Be creative man, you will like it a lot better if you know it is completely yours!