The extreme winter conditions in Japan (sinking below 0˚) have made them invent pretty innovative products. We don’t say that is the only reason for their innovativeness and hard work that has a deeper association with their genetic composition. Here’s a product that keeps your sole warm even in the coldest of winter days. It is called Hokahoka (can’t figure out what that means, but it directly translates as “hot-hot” in my senseless dictionary) and it is an insole that fits into any shoe and the sole with the center heater can be “charged” by a AA battery. It gives a battery life of 7 hours, which is pretty good.
You don’t even have to worry about your foot size as the sole can be cut into the desired size. You could buy your pair of warm feet from Thanko for 20 bucks.