Here's a concept for textbooks that's almost as cool as library checkouts. It's called TextBookFlix, and as the name would suggest, it's pretty much like Netflix for textbooks--with a twist. There's no monthly subscription fee, just a one-time fee to "check out" a book for an entire semester. It's kind of a hybrid between the "no late fees" mentality of Netflix, and the loaner system you get with libraries. The service already has more than two million titles available and a search tool that lets you find your books via ISBN, author, title, or by course.
Cheapskates might not be getting off scot-free however. You're not paying full prices, but many of the books still aren't "cheap." In my testing I found that TextBookFlix was saving about 50 to 60 percent on the retail price on the large, reference-style textbooks--which means you still end up paying a hefty price (more than three pizzas) on a $130-plus textbook. For the smaller titles priced less than $50, the price is a little less. A lot depends on whether or not the titles are new, along with the discount that's been generated.
As a recent college grad, I remember all too well having to buy absurdly expensive textbooks that are now sitting vacantly in some storage boxes in my closet. While book swaps and intercampus book purchase programs are handy, services like this would be great for some of the titles that you know you're not going to be using come the end of semester.