Thing 11 is a self-cataloger called Library Thing. You can share your favorite books with other Library Thing members and the world via your blog. It allows people a window into the books that made you who you are. Also, like most 2.0 things you can tag the books, titles and authors.
I added a link in my sidebar to my LibraryThing list. Check out a couple of the books that I have read.
Now, if I could only remember most of the books that I have read in my life. As I remember them, I will add them to my library thing. This is a great memory jogger for my reading life. Too bad the free stops at 100 books.