Flash Gordon, look out. NASA, hold the launch. It's time to put on your moon boots and stretch out for a freeze-dried cold one inside the superdurable, climate-controlled Hypertat, a "new category of shelter." Missouri-based Hypertat corporation and designer Michael Jantzen have taken five years to develop the Hypertat structure, and they have great plans for it. It can be used most anywhere; its design is versatile and energy-efficient. From what the manufacturers claim, the Hypertat can take care of any remote-site living requirements, except maybe gassing up your dune buggy or sending out for pizza. Hypertat Corporation must be doing something right. NASA just bought one of these modular-shelter buildings to conduct research on experimental plants for purifying water and