I just picked up Neil Gaiman's Smoke and Mirrors - great book, but the cover is purple, with silver lettering, giving it the aura of a cheap supermarket romance novel. How am I supposed to read that on the subway? (See? This really is a traffic-related idea...) A couple years ago, Filth (Irvine Welsh) came out in a choice of blue, green, yellow, and pink covers. Why can't choices like this be available for all books? Even better, design a machine that will allow you to apply your...