Does déjà vu hint at parallel universes? Is it evidence of reincarnation from a past life? Or is it simply a curious mental error, a telltale glitch in our brain that hints at the architecture of the mind? It depends on who you ask. Déjà vu invokes a sudden sensation of familiarity, most commonly in response to a scene, but the stimulus could also be a person, place, or even just a passing thought.

Like a monster trash compactor stretching from the ground to the heavens, tornadoes descend with little warning from the planet’s scariest storms, taking just a few minutes to ruin thousands of lives. F5 tornado Elie Manitoba 2007 (Photo credit : Justin-Hobson - Wikipedia) Like any natural disaster worth its salt, tornadoes remind us of how puny we humans and our built structures really are. Here are 12 cool facts about tornadoes to keep you from getting bored as you crouch in a dank, dark cellar hiding from the most violent storm on the planet.