A Master of Disguise

That the octopus evolved to camouflage itself so perfectly is amazing enough (they use specialized skin cells which can change color, opacity, and reflectiveness), but it's even more incredible when you learn that these animals do not possess color vision:

Did you know that an octupus can learn to open screw-on containers? Here are other interesting facts about octopuses (no, the plural is not octopi). Wired Science has some fun animal videos.