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I plan on putting the towels in my dryer and let them heat up for a bit. I wonder if you put warm towels in an ice chest....would that keep them warm for an hour? If not I may hop out pull them out of the dryer and hand them out. Someone has to sacrafice their body......
also, you can make cheap heating bags by filling socks with uncooked rice and sewing the top and throwing them in the microwave for a couple of minutes. I think if you start out with warmth in the cooler it should keep for some time.