traveling books

This site called bookcrossing.com tracks books that are "released" and "captured," i.e. left somewhere and picked up by someone else who checks it in on the website. It reminds me of a literary version of Where's George. I think it's a nice concept, but I am too lazy to register any books on it. Plus, I have of late been selling anything on Ebay that I think I can get a buck or two for. So, I'm more likely to sell books than "release" them if it's not going to be to a friend or family member.