P vs. NP animation

I’ve been playing with some ideas for a cover for my book, and I ended up making an animation about P vs. NP. It’s on my homepage (I can’t embed javascript here). Click on a nail and see what happens; you can also move the chain to create other configurations. I was looking for something which was connected to the math in the book, and also visually appealing (?), and also related to the grand challenges in complexity theory, and on top of all of this something related to the (somewhat unorthodox) viewpoints expressed in the book. Any comment or other suggestions for the book cover (or the book itself) always welcome! By Manu