BooksOnBoard is carrying the DRM-free audiobooks now... and they're offering Dennis Miller's
Ranting Again for free in the DRM-free MP3 format, which I thought was hilarious - I guess no one wanted to buy it? Here's the link if you want to download it (although I can't imagine wanting to listen to Dennis Miller rant for several hours...):
link to Dennis Miller's Ranting Again in DRM-free MP3 audio book