Megaleledone setebos, a shallow-water circum-Antarctic species from the Southern Ocean. It is the closest living relative to deep-sea octopuses. The specimen shown is a juvenile; adults reach a total length of nearly 1m.
Dumbo Octopus .. The octopuses of the genus Grimpoteuthis are also known as Dumbo octopuses from the ear-like fins protruding from the top of their head-like bodies, resembling the ears of Walt Disney's flying elephant Dumbo. They are bathyal creatures, living at extreme depths of 3,000 to 4,000 metres (9,800 to 13,000 ft), with some living up to 7,000 metres (23,000 ft) below sea level, which is the deepest of any known octopus.
Vampire Squid Vampyroteuthis infernalis, not because it sucks blood but "because they have the ability to ‘cape’ themselves up with their membrane, which is black underside, looking just like a vampire wearing a black cape!"