If you've never heard of the site Pandora.com, quit reading this, put on your headphones and go there now.
OK now that you're back you've realized what a site you've been missing. Simply type in a song, artist, or genre and Pandora creates a "radio" station for you based on the information.
I've been using Pandora for around 6 months and I love it, it's introduced me to a ton of new music. If you hear something you like you can use links to buy from Amazon or ITunes, or you can bookmark the artist or song and return to it later.
If you have an IPhone, Pandora has an application you need to download. The Pandora App gives you a great IPhone interface. I even listen to it over my car's audio system and it works great on AT&T's Edge network.
Bottom line, Pandora's free and will give you endless hours of listening enjoyment.

