My new web2.0 addiction this week comes from Librarything. I'd been thnking that a book tagging community site would be a great idea. Librarything is that great idea.
It's simplicity that makes this website so user-friendly. You only need to supply a username and password to set up your account. From there you can start catalogging your books within seconds. You then use Librarything to find other people with similar collection, get recommendations from people with your tastes, etc. etc. You can also search for new books by tags, to discover the best books to read in any topic.
There's nothing new here. Librarything is just like flickr, del.icio.us and every other social tagging site around. But it's simple, it's easy to use, and almost all of us read, so it has the potential to appeal to a big audience.
Here's the orignial TechCrunch review from last year.