The Sleeping Bag in a Can Was Real and Fantastic

During the Cold War, the U.S. Air Force issued sleeping bags in “spam cans”—steel cans opened with a metal key. Unintentionally silly by today’s standards, it was part of a serious effort to keep crashed or shot-down airmen alive in cold regions until they were rescued.
Read more: http://www.popularmechanics.com/military/a14532075/air-force-sleeping-bag-in-a-can/?source=Snapzu