The Hand Held Protable Air Conditioner is a great little gadget to keep around. It operates on the same concept as a swamp cooler but instead of filling it with water, you wet a sponge insert. I will work with whatever temperature water you add but the colder the water the better.
A quick thing that we've learned from our customers is to dampen the sponge and then freeze it. This will give you ice cold air. It's very small so don't expect it to keep a big tent cool but if you're looking for something to cool you down during a long hike or even if you've just been in the sun too long then this will do the trick.
It has an internal rechargeable battery that is charged via a USB cable. An internal stainless steel stand folds out if you'd like to put it on a desk, table, or chair. It is very simple to operate and clean and even though it is small, it works really well.