Audible, an audiobook service provided by Amazon, had a free trial offer, so I took the offer. I was actually tempted, at first, to continue membership just to get the digital audiobooks. However, I found way too many things wrong with it.
That said, after cancelling membership, I got to keep free copies of "Hitchhiker's Guide to the Galaxy" and "Wizard's First Rule" on my Sansa Fuze.
Dont forget your towel!!!
I never forget my towel. In fact, I have a spare.