ReadItSwapIt.co.uk - Free UK-based Book Exchange

ReadItSwapIt is a free online book exchange. How it works: a) you have old books that you wouldn't mind swapping for some new old books b) you register with the site and list the books you no longer want c) search for books that you do want in the Library section and click on 'Swap with this member' d) said member receives the request along with your registered booklist e) if the user finds a book he/she likes both parties send their books via snail mail and it's a done deal. Of course if someone fancies a book on your list, but they themselves have nothing that even elicits your curiousity, you can refuse outright. While the SwapIt doesn't charge a fee for using its service, you will of course be responsible for paying postage fees. UK residents only.

"Welcome to ReadItSwapIt. We have 135918 books available, with many more added each day.
ReadItSwapIt is a completely free service. If you're a book-lover who likes to swap books or get new books for free, this is the book swap site for you."

This is a really simple yet brilliant concept. Books aren't exactly cheap, even second hand books can be rather pricey. However with SwapIt you can get rid of those books you no longer want and get something that actually interests you in return. The selection is pretty diverse too; it's not all bad romance fiction and sci-fi—there's actually interesting books in there. And its all free, postage notwithstanding.

Is there a rating system for swappers? Is there any sort of guarantee if you don't get the book you wanted?