From the Ivanhoe project I heard about this neat site on altered books. The idea is:
Cut the bindings off of books found at a used book store. Find poems in the pages by the process of obliteration. Put pages in the mail and send them all around the world. Lather, rinse, repeat. This site is a chronicle of a very specific set of collaborations between the artists listed below working on the titles listed below.
They have a number of images of altered pages that are reminiscent of Tom Phillips: A Humument.