John Murphy. Also known as Danny Boyle's go-to guy.
Yeah, this guy composed the theme for the film Sunshine, (the most inspirational, awe-inspiring theme I've ever heard) and the 28 Days Later theme (the most void of hope, defeated theme I've ever heard, while at the same time, inspiring. Figure that one out.) I'd post the songs, but I'm on my Droid, so I'm not going to mess with it. Just if you haven't heard them for some reason, go do it now.
If not him, Tuomas Holopainen of Nightwish. Guy is a freaking genius who's musical capabilities are nearly unmatched, and because of it, is totally forgiven for any mistakes he ever makes (Anette Olzen).
EDIT: Fuck it, here's the songs.
I feel like I can do anything when I listen to this song.
I feel like I can't do a thing to this song, but that I should still try.