I have nothing against the idea of using high tech means to keep toes and hands warm, and my intent is not to criticize others' choices- but to simply post my own view- I personally don't like the 'throwaway society' concept of repeatedly buying plastic pouches that are only good for one or two uses and can't even be recycled- just more plastic non-biodegradable crap for the landfills. I'm waiting (and hoping) for them to come out with slender little wireless heating pads for gloves and boots that use rechargeable power and aren't too bulky. Meanwhile, I use lots of layers of wool and other insulation materials and do the best I can with that. Wearing well insulated winter hiking boots helps me a lot.