Note: Before I begin I just want to say I have not tried the service yet but I figured I would post about it and if someone else has used it they could comment on their experience.
Not too long ago we had a yard sale to reclaim some space. After we left a message on Craigslist for people to come and claim the rest of it. Finally I boxed up the detritus and carted it off for donation. As I did I noticed how many books were still in the pile. Now I must say I have tried offloading unwanted books on places like eBay, with no real luck, and instead I just do the donation thing. However in the future I may give Cash4books a try. The site pays you for your books, that is if they want them. All you do is pop over to the site type in the ISBN numbers from your books and hit enter. If they are interested it will tell you how much they will buy them for. I looked around my office for some test subjects and every book I typed in was rejected. So I walked into the library and grabbed a fairly new book off the shelf. Finally I got one. They would pay me a whopping $1.73 for a Fairly new book. Now I agree that does not seem like a great deal but we have a ton of books at home that we go through from book sales, friends castoffs or just curb pickups and this might be a deal to recoup some of the cost. Once they identify books and they give you a price you need to sign up and then agree to their terms. Finally you print out an invoice and a shipping label. They pay for all of the shipping. I liked this hassle free approach. You box them up and they pay you by either check or the service Paypal. So in future just before you donate all your books you may want to try the service at least once.