OK, here is one for the  über concert goers out there (are you listening Michael?). It is called Podbop.
Here is the deal, you feed it the city and it will serch it’s database of bands coming to your area in the near future, grab a sample of music from that band and wrap it all up in a nice little RSS feed for you. Then you can not only know who is coming to town but also see if you think they are worth checking out. A great way to discover new music and live concerts.