Do you like sci-fi?
Do you like comedy channels?
Do you like talk shows?
Do you like new content all the time?
Do you have an iPod/any MP3 player?
Do you have iTunes on your computer?
Then Podcasts might be for you!
If you have iTunes 4.9, there's a new feature on the left panel called Podcasts. Go look at the podcast channels (there's a link below for the iTunes window for that.) You can subscribe to any channel that you like depending on your interests. It's all for free!
I've been listening to Michael and Evo's Dragon Page, Slice of Sci-Fi, Monk and Dave, Z100 Phone Taps, etc. I might end up putting more podcasts than music on my iPod. :-)
I drove to New Orleans last weekend just listening to podcasts. That's a 6-hour drive and I didn't run out of stuff to listen to. I just did the same thing driving back.
If you don't have an iPod/MP3 player, then just listen with your computer.
Try it out!