What is the name of the site that people leave books in places that others can find across the US and read?

I know there is a site, but I don't know what it is. But what's to stop you from starting something like this yourself? Just take a book you read and liked, enclose a piece of paper explaining "take this book if you want to, read it, then pass it along by leaving it in some public place (with or without your comments)". I picked up a (not very good, actually) book this way at a coffee place a few months back and it made me think what a good idea this is. So I not only passed on the one that was passed on to me, I sent one of mine out to seek its fortune as well. I really don't think you need a website for this--the spontaneity is part of the fun. :)

I'm not positive, but are you talking about geo-caching? Theres probably quite a number of sites dedicated to it, and I could easily see one specifically about books.

read it forward

190,000,000 results come up in a search

maybe they got it from that movie pay it forward

idk, when you find out, tell me , because thats cool