This is a new one on me. Some libraries have been having Edible Book contests. For example, this is A CLOCKWORK ORANGE by Jeanne Mithen, from the 2007 contest atTopeka and Shawnee County Public Library.
I discovered this when I came across the 2009 contest at Staley Library of Millikin University. I can't copy their pictures here easily but go look at them, especially Eric McKinney's little masterpiece.