Taylor Hamilton has come up with a great idea to reuse skateboards. He made a bookshelf system of a bunch of them. Definitely, why not to do that? Each skateboard can support a human body so it definitely could support a bunch of books. If you want to make such bookshelves by yourself you should know some things.
First of all you can always renovate old skateboards using spray paint and decoupage techniques. That means that you can buy skateboards on garage sales for cheap for such project. The second thing you need to know is that the arrangement is the key to success here. Try to capture the movement if you succeed your bookshelf system will turn out great.