I couldn't resist mentioning this little project here.
Being inspired of fore-edge paintings, we at 2Krogh have begun experimenting a little with the phenomena - digitally.
So far I have created two test cases on plain copy paper and I simply love the idea of illustrating the book block, check it out:
Pure text "painting".
A coloured illustration.
I can't wait to try this "full-size"! I will of course be posting pictures as soon as we have made the first book with this exciting feature.