A drop bear (or dropbear) is a fictitious Australian marsupial. Drop bears are commonly said to be unusually large, vicious, carnivorous koalas that inhabit treetops and attack their prey by dropping onto their heads from above. They are an example of local lore intended to frighten and confuse outsiders and amuse locals, similar to the jackalope, hoop snake, wild haggis, or snipe. It is often suggested that doing ridiculous things like having forks in the hair or Vegemite or toothpaste spread behind the ears will deter the creatures, or that walking through the bush carrying a screwdriver raised above one's head will impale an attacking drop bear.
Wikipedia bitch.....If they were real they would be awesome :(