A TV show in Brazil recently pulled off a pretty mean elevator prank. First they rigged the elevator with hidden cameras, and waited for someone to get in. Once the elevator was moving, they'd cut the lights for a few seconds.

And when they came back on, a little girl in horror movie make-up would be standing next to them and would start SCREAMING. Then the lights would cut out again, and she'd disappear. The girl got in by crawling through a hidden panel.

The best reactions are at 1:45, 3:50, and 5:52.  But one of the women at 5:05 doesn't seem to fall for it.