Why We Want One: A huge population of these guys were just discovered in an undersea vent near Antarctica, and scientists have nicknamed them "Hasselhoff Crabs" due to their distinctly hairy chests. How cute is that?

Why We Can't Have One: Hasselhoff Crabs thrive in Antarctic water 2500 feet below the surface. Not exactly easy to recreate these conditions with an aquarium from PetSmart.