The Sea Hare

This is a Sea Hare

          Like their snail cousins, sea hares are soft, plump and slow. These creatures -- so named because their tentacles resemble rabbit ears -- graze on algae and sea grass in coastal waters. But like slugs, sea hares have no shell to hide in. When faced with a predator such as a crab or spiny lobster, some sea hares blast the attacker with a defensive spray, a combination of dark purple ink and a shimmery whitish substance called opaline.  This is the first time researchers have describe an animal that can take photosynthetic pigment from its diet and turn it into a molecule that can wield off would-be attackers.... 

http://news.discovery.com/animals/sea-hare-chemical-weapon.html

it's pretty cool how strange and yet resourceful animals can be.