I listen to everything. Except rap (with the exception of Will Smith, the Beastie Boys, and Anthrax (who's da man)).

Classic rock, metal, classical, Motown, big band, martial music, some country, some punk, some new wave, and my wife and son (who are both far more cool than I) keep my ipod loaded with the current hot bands.

When I'm on a project though, I tend to go to what relaxes me. Celtic Woman/Thunder, Earth Wind and Fire, G. Lightfoot, Neil Diamond, Amy MacDonald (Scottish girl who I can't get enough of), that kind of stuff. An old favorite that I can't find on CD is Roger Whittaker.

When driving, if my ipod dies, I generally just put the radio on scan. Continuous 6 second bits of whatever is on generally amuses me.