i just started using audio scrobbler and i’m intrigued by it. basically it is a plug-in that you add to your media player (real player, itunes, etc. – just don’t use micro$oft’s media player) and it then keeps track of the songs you listen to and will post them on the web for others to view. if you are really into electronic privacy this is not the website for you. anyways, after a while of tracking your musical tastes the website can make educated suggestions of other artists you would like (this could definitely be abused by a music industry desperate to get you to buy their latest stuff but it could also be a cool way of experiencing new artists) and it will recommend other people who have the same musical taste as you. personally i just want to see what i listen to the most. of course, it is going to take a few weeks for it to really get an idea of what music i really like.
you can view my current musical listenings at http://www.audioscrobbler.com/user/ratterrell/.