If you haven't discovered the joys of podcasts yet, you should get on the ball. Podcasts are audio files set up in a serialized format that you can listen to on the go with an mp3 player, or sitting at your computer. Despite the name, there's no requirement to own an iPod in order to listen to a podcast.
Think of it as radio on demand - you can select what you want to listen to, and where you want to listen to it. You get customized updates sent right to your feedreader or music interface, such as iTunes. You don't need a Mac or an iPod to use iTunes - it works with everyone's music and audio files and it's quite simple to us.
One podcast that I subscribe to (and highly recommend) is the Radio Detective Story Hour with Jim Widner. Each week, he spends a few minutes giving an introduction to the series he is highlighting. Up until episode 68, he rarely repeated a subject. Currently, he's on a multi-part series of "Yours Truly, Johnny Dollar."
Sherlockians might like to listen to a radio adaptation of Sir Arthur Conan Doyle's short story The Lost Special, which first appeared in print in 1908. The Radio Detective Story Hour features the only appearance of Inspector Collins of Scotland Yard.
Go directly to the Radio Detective Story Hour page about Inspector Collins or
Listen to/download the episode
If you have any questions on this technology or on subscribing to the show, just let me know. I'd be happy to help.