Keeping track of your books

I recently found Library Thing, a clever way to keep online records of books you've read or those you own. I have a pretty complete inventory of my books on Microsoft Access, but I don't record the "escape reading." As a consequence, I can never remember if I've already read that Harlen Coben or Patricia Cornwell when I see it at the library. You can list up to 200 books free, then there's a membership fee. The site has some interesting features for Bookaholics and a free tour shows how it works.