As an avid fan of Pandora for a long time, I think I am finally converted to Slacker. Pandora is cool in theory. It lets everyone vote on a song and can select similar music for you. I can honestly say I listened to things I would have never chosen because of it. That's kind of it's downfall also. I HAD to listen to some weird stuff I didn't like.

With slacker you can create a station of things that you like. This has the same skip limitations, but I find I don't skip much. They have programmed stations, but they seem to repeat themselves a lot. I will probably still listen to Pandora when I am in the mood to be adventurous, but for my "coding" music I much prefer Slacker. Check it out.