Beware the oceans! Out there are swarms of KILLER jelly fish!!
Jelly fish the size of fridges, jelly fish that kill in minutes, jelly fish that create dead zones around our planet!!!
And what is really scary is that its all true.
See summary from The Register here and the original National Science Foundation flash based special report here.
I think its all to do with us humans killing off the animals that eat jelly fish (things like turtles, sharks, and sunfish) - bit of a mistake really.