Having an MP3 player is wonderful! In addition to all the music, I have been listening to some great podcasts. Really only two so far, but I'm hoping to keep my podcast subscriptions to a reasonable number (something I can't seem to do with my blog subscriptions). So, for your listening pleasure, I suggest you check out:
Science Update Podcast - This weekly podcast gives updates on things going on in the science world, from nifty things such as the Harry Potter invisibility cloak being a possibility in the future to a chewing gum that fights cancer. They are pretty short - maybe 5-6 minutes per weekly podcast. A nice quick update of some very cool stuff.
FLOSS Weekly - This one is probably something most of you won't be interested in but I find it fascinating. It's all about open source stuff. Each podcast is an hour long. So far I've listened to Ryan Gordon talk about porting games to Linux, Jimmy Wales talk about Wikipedia, and earlier today I listened to Ben Goodger talk about Firefox. The Jimmy Wales interview was all over the library blogs a while ago. Good stuff!
And now I'm done sounding like an advertisement for podcasts... :)
To subscribe to these podcasts, I'm using Juice. I had to resort to Winamp though to get the older ones. I had my Juice preferences set up to skip old podcasts permanently and that didn't work so well when I wanted to listen to the Firefox and Wikipedia ones.