Goblin sharks look scary as hell and are scary as hell. Sure they're only a couple feet long, but they're uglier than my sister and have tons of sharp little teeth. Watch the video around 0:20 to see how it's mouth comes out of its face Aliens style to munch on dude's arm. Also, a friend told me that's what a woman's vagina looks like.
The Goblin Shark [Youtube]
Thanks to Libby, who once punched a goblin shark in the mouth because it looked at her funny.