Sure, the idea of smart shoe insoles may sound a tad ridiculous when just about everything tracks our steps. But how about insoles that can also warm up your toes? We had a chance to try out the Digitsole warming smart insoles at CES, and while they weren't world-changing enough for us to drop $200 on them, they certainly worked as advertised. I felt my foot gradually warm up to the point of toasty when I tested them, as if I was sitting in front of a roaring fire (except I was actually standing in a chilly Las Vegas convention room). Digitsole can reach up to 120 degrees Fahrenheit, and its battery (rechargeable via USB) lasts six to nine hours. You can control the temperature via an iPhone or Android app, which is also where you can track the amount of steps you've taken and calories burned.