This looks like a great place to hide…

The veined octopus (Amphioctopus marginatus), also known as the coconut octopus, has a skill beyond other cephalopods: it hides under animal and coconut shells, dragging them along the seafloor for protection. This is one of the few examples—if not the only example—of tool use in invertebrates.

Credit: Jeffrey de Guzman/Nature’s Best Photography