This inverted bookshelf on Instructables hangs all of the books from the bottom without damaging the books by holding them together with elasticized strips of cloth.

The intention was to create a cool twist on the regular book shelf, but since people now are interested in multifunctional products that save space and money, and innovative ways of storing their beloved books, this product could act as a double capacity bookshelf that holds books from the top and the bottom.