Then they changed formats. Either you paid a membership fee, or you paid a small a la carte fee each time you request a book.
Adding the fees to the shipping price just added up to books from PaperBackSwap not being sufficiently cheaper than just buying used books. Yeah, it made it easier to find the books, but going to the post office will always be more annoying than going to the book shop, let's be real.
So here's what I'm going to do. Below, please find a list of books I've placed on my 'Up for Grabs" bookshelf on Goodreads. If you know me well enough in meatspace to exchange holiday cards, then you are welcome -- even encouraged -- to request a book off this shelf (and if you want to unload some books of your own, feel free to send me a list of titles).