Will Google ever stop coming up with new ideas. How about this one - a virtual book library!
Have you ever tried remembering where you read something somewhere, and now you've got to hunt down the book? Well, this would probably help. You can check out Google Books Library here.
On a rainy, slow weekend I think I might just capture my collection.
And for the real techno-junkies - how about doing it with a bar code scanner.