I don't really have one. I put it on shuffle and skip anything that doesn't work, but I'm all over the place. Sometimes it's classical (so I can think) and sometimes it's Rage Against the Machine.
Running to classical?! lol
See, you have some angry liberal music you run to! hehe
I'm usually swearing t the tv during my workouts, so the music fits.
BTW, it's about time you got to work.