Crissy Huffard and Robert Full of UC Berkeley discovered that some species of octopus have evolved a neat trick to run away from predators: they lift six of their arms and walk backwards on the other two!
When walking, these octopuses use the outer halves of their two back arms like tank treads, alternately laying down a sucker edge and rolling it along the ground. In Indonesia, for example, the coconut octopus looks like a coconut tiptoeing along the ocean bottom, six of its arms wrapped tightly around its body.