Lately I have been using a neat little application called the "Last.fm player" which is available from the website last.fm. You enter in a band or artists name and then it creates a streaming radio station for you with bands similar to that which you selected. Pretty neat overall.
Today I was turned on to an even cooler site that does the same thing, but so far, it does it better. It's pandora. So far I like it better because it runs in my browser (no new app to install) AND it seems to give me music that better fits style of the group I entered. For instance when I entered "Pink Floyd" it gave me some really cool music by The Smiths and Scott Walker which both have a similar feel to different periods in Pink Floyd's musical history. The Scott Walker song is kind of like real early Pink Floyd and thus a little wierder. The Smiths are more refined sounding and are closer to the "Division Bell" Floyd that appealed to a wider range of music fans than the real early stuff did.
The one thing both do well is they let you skip over any song you don't like. Most streaming radio you listen to forces you to listen to the entire stream so you're stuck listening to the crap along with the gems. That isn't the case with last.fm and pandora. Hear crap? just hit skip and bam you are on a new song. Very cool