Thinking of buying a new MP3?

Awhile back I started getting into the Deathland series of audio books from this website. http://www.graphicaudio.net/ However much to my dismay I found out that due to the licensing software they use their files can't be played unless Windows software is used. To the best of my knowledge you can't play their books on an I-pod without taking drastic measures.

This is the only case like this I've run across myself and since most people have never heard of these books  it shouldn't be a direct issue for anyone else but me. Still I thought I'd throw it out there so you all will know it's a possible problem depending on what you want to play.