Here's some visual fun. Cephlapods - squid, octopus, and cuttlefish - have incredible color-changing capabilities. Add to that, the ability of the octopus and the cuttlefish to change the texture of their skin and you have some remarkable displays of camouflage.
Below is a great short video from Science Friday, originally put out by the educational arm of the Woods Hole Oceanographic Institution. The actual footage was shot over a decade ago by marine biologist Roger Hanlon and I have seen it in other Woods Hole presentations over the years, but it never loses the fascination it generates with the viewer.
Not only is it amazing to watch but it's also mysterious - scientists to this day are still trying to determine how these mollusks are able to do it. How can a colorblind octopus match its color to the surroundings so perfectly? What triggers the type of display the animal will use - a communicating color pattern, a camouflage pattern based on color or texture or both?
Aaah, the mysteries of the deep. . .