It's a dirty secret, but I have a sordid affair with trendy American Pop...I railed against it all through Middle/High School but now in my later years I've simply come to accept that my musical tastes are generally shallow. As it is, I only really listen to music while I drive, and something with a driving bass line and an upbeat tempo compliments my speedy bob-and-weave approach to driving.
That being said, sometimes while I'm on my computer I'll wizz over to Youtube and bring up some great Orchestral music to feed the creative juices. Depending on my mood, it may be some John Williams (Star Wars, Jurassic Park, etc.) or some more classical composers (Orff, Tchaikovsky, etc.). All in all I don't really listen to music too often.