Since we are going off on a tangent, a cool camping hack when you don't have ice is to stuff a beer in a tube sock, dunk it in water, and hang/tie it to a tree branch in the shade. If there is even a touch of wind it will be nice and cold in 10 minutes.
Evaporative beer cooling.. very clever. I wonder if there is a market for a product dedicated/optimized for this (incorporated drawstring/hanger, ideal material, etc.)