Here is a video version of how to make the world's cheapest and easiest refrigerator from two terracotta pots. It uses minimal resources and runs completely without electricity. It's called a zeer pot, or the pot-in-pot and was rebirthed by Mohammed Bah Abba, who put the laws of thermodynamics to work for mankind.
Patrick Whitefield previously posted a solution here on permaculture.co.uk describing how to make this simple device but here is a visiual/auditory how to with the added advantage of some temperature testing on a hot day in the USA at the end. You'll be suitably impressed at how cold this design gets.
Wonderful! We'll never go camping for more than a week without one.
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