Self-heating shoes. Shoes with electrically-powered heating elements around the toes. Very nice for those of us with poor circulation to the extremities.
Power is the big issue, though. Plug-in cords kinda put a damper on the whole “mobility-enabling” aspect of shoes. Batteries are probably reasonable, if one doesn’t mind changing them every now and then.
My love affair with the notion of piezoelectric energy harvesting leads me to suggest that a few piezo collectors in the soles of shoes could supplement the battery, slowing the rate of turnover.
Some military researchers have looked into piezo-shoes before as a means of powering a full tactical equipment array and found the energy harvested was outweighed by the extra effort that walkers had to put in. Maybe this trade-off ratio would be more manageable if the power didn’t have to be transmitted anywhere and the electrical demands were rather more limited.
