Surf Sauna can build you a warm oasis to accommodate anywhere from two to eight people. They make 'em right on the cold coast of Portsmouth, NH out of Western Red Cedar and marine grade galvanized steel, so they're built to last years of water and salt exposure. And if you don't surf? This thing works outside the ski lodge as well, folks.
Ethan Wolff-Mann is the Gear editor of Supercompressor. He finds it incomprehensible that people can go into the winter waters of New England. Follow him on Twitter @ewolffmann.