Most people believe that wrist-worn wearables are technology's next frontier, but only one company that we know of has thought about our feet. Today, that number increases to two, now that Digitsole has announced an interactive insole that's designed to heat your feet. Connecting to your smartphone over Bluetooth 4.0, you use the companion app for iOS or Android to set the temperature to a maximum of 40 C/104 F. Of course, no piece of wearable technology is complete without some sort of activity tracking, so in addition to keeping your little piggies warm, the smart insoles will monitor the distance that you've walked and the calories that you've burned.

Hardware-wise, we're looking at an insole weighing around 3.5 ounces, with a Neotech heel, which is good for preventing vibration, and a Poron sole that we're told is a good shock absorber. The battery is sandwiched inside, charges over microUSB and has a rated life of between 7 hours and a few days, depending on use. Unfortunately, you can't buy Digitsole at the Sharper Image, at least not yet, and instead will have to buy one through Kickstarter. Super early-bird users will be able to get a pair for $100, while Johnny-come-lateleys will rue their cold feet (geddit?) after spending $150.