Actually I'm responsible for a patent for a cooling suit. I developed it for the physiology department of my old university. It used themoelectrics to heat or cool the wearer. It weighed about 20lbs though and you had to drag a control panel and bucket of water around with you everywhere you went. It was designed to be used by somebody just standing or sitting around, or at most riding a stationary bike. It would get very cold though. It could be adjusted anywhere from 'hot enough to cook steak' to 'cold enough to turn blue'. Needless to say I included electronic safeties in the system...
I saw this interesting device, you put compressed air in on hole, then a vortex is formed in the tube, and out of the 2 exit holes, you get burning hot air and freezing cold air. One company made these vests for like steel mill workers, but I forgot witch one.
I watched a special on TV about the US Military and their recent trips to hot climates (Iraq, etc). Some of the troops have water cooled vests similar to what were discussing. I can't remember if the water is within the vest and thus cools the person or not. To be honest, I can't remember the specific concept, but they have vests and something to do with water! HA! Now there's an educated statement! Just thought you'd like to know.