This is an idea for a winter coat that generates heat through bodily motion. There is a couple ways this is possible. The first is to use coarse or elastic materials that rub together to generate heat directly through friction. These materials could be overlapping plates in the back of the jacket that slide across eachother as the arms of the wearer pendulate.
The second possibility is much more interesting. If a coat consisting of atleast three layers is constructed then static electricity can be generated. Materials of opposing triboelectric polarity are made to rub together when the wearer is in motion. These constitute the first two layers. The first layer worn close to the body is integrated into an elastic medium that extends and retracts rubbing across the surface of the other. The third layer is seperated from these by air and electric potential discharges across this gap generating heat. An additonal layer can insulate the coat.-- rcarty, Feb 17 2013 In a cold dry climate the static electricity of normal clothing is enough to create a living, staticy hell. I'm replacing all of my clothing with ANTIstatic cloth.-- DIYMatt, Feb 17 2013 It gets a little tedious having to ground myself to kiss my wife.-- Alterother, Feb 17 2013 Perhaps. But think about a coat with elastic bands in the broad back area. These elastic bands are fixed at the centre and the other ends are attached to the inside arms of the jacket, so when the arms pendulate the elastic bands are stretched. The bands generate heat by being stretched and contracted, and by rubbing betwen material they are sandwiched. The draw weight of the bands is approximately ten lbs on each arm. The jacket is insulated for thermal efficiency, and the extra work required is traded for less shivering and less loss of body heat to the cold. Also it can be marketed as an exercise jacket, because people have generally become dumber. Doing this extra work while wearing the jacket will also increase body heat by increasing metabolism.-- rcarty, Feb 17 2013 At first this idea rubbed me the wrong way. Then I saw a small spark of a good idea so overall I'm neutral.-- AusCan531, Feb 17 2013 Good idea for gloves, rubbing the hands it's a natural way to warm them.-- piluso, Feb 17 2013 Proof of concept.-- rcarty, Feb 17 2013 Wonders how this works in burka-territory-- not_morrison_rm, Feb 18 2013 So, when it's too dark for the photons to warm up the morons they have to get electrons to do it?-- UnaBubba, Feb 18 2013 / But think about a coat with elastic bands in the broad back area./ We tried this at BUNGCO a few years back. However the suppressed bra-snapping urges of many of our employees surged forth in an uncontrollable way. Many died, and so the coats are now with other similarly dangerous inventions in the Danger Vault, accessible only to supervillians bent on world domination.-- bungston, Feb 18 2013 /just being 4 times the size I was aged / On the contrary!-- bungston, Feb 18 2013 The elastic coat design with the bands in the back could be operated by pulling cords in the sleeves by hand when necessary.-- rcarty, Feb 18 2013 random, halfbakery