My entire english class played this during class involving my teacher and whoever came in the classroom, all of us will stare at the person with serious faces and our teacher will say sternly "The floor is lava. Climb the desks".
Funny thing: Whenever watching a movie like jaws, or watching a series like River Monsters (where there are some very scary fish and such), I HAVE to keep my feet up. I have to curl up, with my legs in my seat. Otherwise, the sharks will eat my legs. O_O