In fact, untill recently the only way you were
allowed to buy eBooks from Amazon was if you had a registred Kindle / iPod-Kindle-app linked to your account. I tried to buy a book from them a few months ago, figuring the DRM would be removable, but without a registred Kindle there was just no way.
Mind you, that's exactly the kind of monopolistic thinking that made me buy a Sony reader instead
