Wear your book on your sleeve! Or, probably better, the lapel of your jean jacket.
Ideal Bookshelf has captured the essence of a book in less than an inch square.
Each badge is a hard enamel lapel pin with raised gold-plated outlines. It's about 1 inch tall by 0.75 inches wide, and attaches to your clothing with a black rubber clutch. It ships pinned to a small cardboard plaque.
This one is of Douglas Adams' hilarious The Hitchhiker's Guide to the Galaxy, and remember, the answer to the question of Life, the Universe, and Everything is 42.
Based on an original drawing by Jane Mount.