I've been saying on the site how much I hooked on my Amazon Kindle. But from the beginning my big worry has been the market power -- arbitrary power -- this gives Amazon over your entire book collection. Here's a story about a guy who bought a Kindle, liked it, used it, etc. But then Amazon decided he'd returned too many real world items. So they turned off his Amazon account, thus making his $300-plus Kindle into a mostly useless piece of plastic. He had to spend a lot of time begging and pleading with Amazon customer service to be allowed to use his Kindle again.