I go camping often and I bring food that requires to be cold in a cooler. Instead of getting bags of ice every time I go, I came up with an idea of putting 3 completely frozen water (gallon) jugs in cooler and they lasted a few days! No watery mess and when jugs are thawed, it can be used for drinking or cleaning.
I also reuse plastic juice containers with frozen water so it will lay flat and fit neatly in bottom of cooler. This works a bit better than gallon jugs.
[Kacie posted this tip to the Readers’ Tips box. It originally appeared as a comment in The Complete Tightwad Gazette giveaway.]