Podcasting is the new-ish big thing. Thanks to broadband people are now using Really Simple Syndication (RSS) to blog regular audio pieces. Some of these are music (new bands, DJs, etc) and a lot are spoken word.
To that I would add some of my own favorite sites:
I’m sure a lot more will be along soon. I’m looking forward to the day when backstage.bbc.co.uk will have feeds of all the “listen again” MP3s on the Radio Four site.