Imagine a power source for cellular telephones and other portable electronics at half the weight of nickel cadmium batteries, same cost, yet with 50 times more energy. Those are only some of the benefits of miniature-fuel-cell prototypes demonstrated by inventor Bob Hockaday. He says his micro fuel cells should last at least 20 years and can be refueled simply by pouring in 1.5 ounces of inexpensive methanol -- instead of waiting a day while a battery recharges. Also, he cites significantly less environmental impact at disposal time. To realize the technology's potential, he has formed Energy Related Devices Inc. (505-662-0660) and estimates that the fuel cells could be on the market in late 1999. Initial funding has come from Manhattan Scientifics Inc., a publicly traded company located in Los Alamos and New York.