From an article about a snowboarder who was lost for a couple days:

Boucher said he survived the freezing nights in the hazardous North Shore wilderness, in part, by using his own urine in a Ziploc bag as a kind of hot water bottle.

Seems pretty clever to me.
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Victory awaits him who has everything in order — luck, people call it. Defeat is certain for him who has neglected to take the necessary precautions in time; this is called bad luck. Roald Amundsen