Ah yeah! Haven’t played with it in depth yet, but this is the service I’ve wanted forever (and Carl and I seriously sat down and threatened to build).
From Joi Ito
It reminds me a bit of BookCrossing, but the approach is different. BookMooch is more systematic. On BookMooch, you register your books and others search for books. You use points to get books that you earn by listing books. Unlike many other used book services, they don’t get involved in the shipping and payment. It’s rather peer-to-peer.