What happens when you throw a pot full of just-boiled water into the -41C air? Dmitry Klimensky in Novosibirsk, Russia demonstrates. From: Mpemba effect — Why hot water can freeze faster than cold:
The effect now known as the Mpemba effect was first noted in the 4th century BC by Aristotle, and many scientists have noted the same phenomenon in the centuries since Aristotle’s time. It was dubbed the Mpemba effect in the 1960s when schoolboy Erasto Mpemba from Tanzania claimed in his science class that ice cream would freeze faster if it was heated first before being put in the freezer. The laughter ended only when a school inspector tried the experiment himself and vindicated him.