See here). I also have a slight obsession with cardboard, and it was right up my alley. My book is smaller than her sample. Most of my boxes on hand were shallow Amazon boxes, so my book is 4 x 6 inches (hers is 5 x 10). I was thrilled to see I had a box from Cheap Joe's - what a great cover that would make!! (And if anyone wants to make a book called Joe's Stuff, I might be able to help you out with the cardboard!)
Fun Factor for this book: 10+!!