Meet Hot Pocket: a heated stuff sack that provides you with warmth on demand in the wild. It can be used to preheat your sleeping bag or instantly warm it. You can use Hot Pocket to charge your phone too. It provides you with 6 hours of heat with auto shut-off.
Hot Pocket is available in 3 sizes. Its power back comes with a 6000 mAh battery. Expected to ship in November.