Years ago I had the idea to start a site where people would build a database of their books, and users could request to borrow each other’s books. There could be a feedback mechanism so you’d know if a person was trustworthy.

I never did anything with it, partially because it seemed like it would be hard to do, and partially because I realized that I really didn’t want to share my books with strangers.

I just noticed ISBNdb, a free database of ISBN numbers and associated data. It’s gathered in a neat way, too — it apparently has spidered libraries across the world and built up a very sizable database. They provide a fairly simple API as well, making it easy to fold into an application.

I’m interested in picking up a cheap barcode reader. I’m curious how they work, but I think that at least some essentially pretend to be a USB “keyboard,” which means it would work nicely with a web app: just make sure your cursor is in a textbox, scan, and viola. I think that would greatly improve the usability, since no one wants to manually key in every ISBN.

I’m still not sure what I think about this book sharing thing, but I’m attracted to the basic concept anyway. Another neat one would just be reviews — scan a book you’ve read and review it.

Is anyone familiar with sites like this already? (Aside from, of course, Amazon.com…)