Pandora radio is the bomb! If you haven't checked it out, you really should.
The concept is simple. You type in a song or band that you like, and Pandora will generate a radio station for you that has similar types of music. I created R.E.M. Radio and Indigo Girls Radio today. I'm encouraged, because the Indigo Girls station played Brandi Carlile and Cowboy Junkies, both of which I also like; it also played an artist I hadn't heard of before, which is a great way to learn about new music.
The best thing about Pandora is that it's free, as long as you can put up with the ads. The worst thing is that it might be the ultimate in ways to procrastinate, which I really don't need. And now I will stop my Pandora ad campaign.