This shirt is cool as far as temperature goes, not cool as far as looks. Unless you’re into a sort of old mattress look. It’s a t-shirt with a water cooling system to keep you from overheating. It’s got an inlet and an outlet on the fifty feet of rubber hose that connect to a pump.
The water circulates and you get to sit in the summer heat without needing air conditioning. It was actually designed to be used by race car drivers. No word on price, but it’s probably pretty expensive. You could probably make your own and actually give it some style. Even the still-suits in Dune had more style then this shirt, plus you could drink your own fluids.