Make instant slushies with supercooling

Sound the alarms: Water doesn't always freeze when it should. In fact, you can chill water and most other liquids below the temperatures at which they usually freeze. Scientists once cooled water down to the frigid temperature of -51°C, and the H2O remained liquid, at least for a fraction of a second, before it flash-froze. But forget scientists—you can use this phenomenon, called supercooling or undercooling, to make instant slushies—even beer slushies.