A cold one

Filling up the dewar which holds 160L of liquid. Liquid nitrogen boils at 77.3 Kelvin, or about -321°F, at room pressure.

You have to be careful with nitrogen because it's not easy to tell if it has displaced the air around you. The common cryogenic liquids are about 700x denser than as a gas, so 1 liter of liquid would evaporate into 0.7 cubic meters of gas.