Leaf Insect
Shhh! Pretend you can't see the bright green critter hanging out in the photo at left. What do you mean you can't find him? As a kind of leaf insect, he mimics the shape, color and texture of leaves. And the guy in this photo is hiding from predators--neighborhood birds who'd love to eat him for lunch.
But not all leaf insects are green. Their appearance depends on the environment they live in. There are brown leaf insects, for example, who are found in flora that's predominantly brown. (P.S. As far as we know, there aren't any rainbow-striped leaf insects.)