Bart's Books (www.bartsbooksojai.com), also in Ojai, has bookshelves on the outside of their building filled with used books for sale. You take the book you want, and then throw your money over the wall to pay for it.

Besides this unique selling method, the rest of Bart's Books is worth a visit. It's a great little used book store, and they always seem to have an author or poet visiting.