Put your trust in AA batteries. The SpareOne mobile phone is a barebones handset that runs on one replaceable AA battery. There's no screen, no charging port, or other ports, but it will give you 10 hours of talk time; the battery will keep for 15 years if the phone isn't used. It's intended for use in natural disasters and other emergencies. There's a number keypad, dial and hang-up buttons, and basic volume control. It also has a small flashlight and an "emergency call" button that automatically dials the local authorities. It weighs 2.6 ounces, and measures 4.72 by 2.36 inches. SpareOne was created by a subsidiary of TennRich International, and is available in the U.S. for $70, via the company's website.