I really like last fm, the have started putting on gigs in london (did acid mother's temple and a few of my friends bands all good) I think it's pretty good for bands too, you can put up streams and MP3's and people may stumble on your goodness.
www.last.fm/user/ians
and my band
http://www.last.fm/music/Econoline
this was a real boon at an old job where I could listen to music at work, now I don't use it so much as I don't like syncing my ipod and mac to the scrobbling, which is what i listen to at work or in the car, but I still like it for the recommendations and free MP3's. Tragically I lost the free MP3 of sleep's Jerusalem in a mac related disaster and then it got taken down! By the way to everyone who stopped using it because people made fun of the stuff you were listening to.. what's the matter with you? Are you 11? I'm going to come round your house and make fun of your trousers will this make you stop wearing them? The only shameful thing about it is when everyone sees that I am the only top listener to my bands.. which means I should stop trying to relearn songs while the audioscrobbling is on.