I just decided to install iTunes with my Quicktime. I've subscribed to some nice nerdy podcasts, but I don't have a credit card, so I can't buy music from the store. I've subscribed to Look at his Butt! (a Trek podcast), Lord of the Rings radio, and TheForce.net. I've also subscribed to (but not yet listened to) Shakespeare-upon-iPod and The Word Nerds.
nerdy
I've just started listening to the Shakespeare one, and it's a guy podcasting his arguments that the Earl of Oxford wrote the plays attributed to Shakespeare. Darn it. :0(
You pay the $10, it gets you a card for 10 songs, and you can access itunes with out the need for a credit card of anysort.