>Oh. My. Gawd.
LibraryThing. An easy easy way to catalog your books online…and do all kinds of fun things, like see what other people who have your books are reading…kinda like a more interactive Amazon.com. One fun feature is the Anti-suggester. You know how Amazon will tell you, “People who bought X also bought Y?” This one says, “If you loved X, you’ll hate Y!”
Tremendous fun. Major time-wasting potential.