I love music, as much as I love writing. I get inspiration from flavors of music, and create stations that evoke the 'feel' of a particular project. Sometimes it's focused around a particular character, other times it's centered around world-building.
One of the things I love about Pandora is that I can create these stations without owning all the music myself. This lets Pandora drive and it's like having my characters take over the radio. It adds to the feeling that the character is a real, and separate, person - which helps me when I'm writing to stay in the point of view of my characters and not my own.
My personal tastes trend all over the map: classic rock, classical guitar, Middle Eastern dance music, Celtic folk music, bluegrass, 80's "alternative," intelligent dance music, etc. About the only things I don't care for are negative rap (I like rap, just not the 'kill kill kill' crap) and singers who can't sing.