Some pretty awesome book shelves. I personally want floor to ceiling shelves covering at least two walls in my spare bedroom. until I upgrade from condo to a house with a full-blown library / reading-n-nook room :D
I see a lot of "almost" bookshelves. They hold books and look "design-y" but they waste energy and space. If you are really into books, it's not about the cute shelves. It's about the books. Make that space hold as many as it can.