I think this is a really cool idea. There’s not an actual shelf but instead you place book on top of book on this "bookshelf".

I don’t know if I would put this in my son’s room for fear that he would grab one of the books in the middle of the stack and the rest would come tumbling down, but I would definitely use these in my office.

Where to buy:  Umbra Store
Cost: approx. $12