The inverted bookshelf turns a bit of your living room upside down as it hangs all of the books from the bottom instead of supporting them from below. It's a satisfying optical trick and doesn't damage any of the books. In fact, you can take books in and out of it whenever you want.
In addition to the basic materials for a shelf of wood and brackets, you will also need elastic webbing and a staple gun. The elastic that I'm using here can stretch beyond 200% of its original size and is certainly strong enough to hold the books here.