Albert Schueller writes "Lulu is a place where authors can self-publish their books. It's a nice response to exorbitant college textbook prices. In an interesting twist, looks like you might be able to get away with selling other people's books on Lulu and reap a tidy profit. The Lulu offering Calculus Twirly Exponentials by Dave Stuart appears to be simply a high quality scan of the much more well-known, and expensive, Calculus: Early Transcendentals 6th ed. by James Stewart. Compare the preview images available for each at Lulu and Amazon respectively."