Forget clocks that tell you what time it is using LCDs, LEDs or mechanical hands; the Thermochromic Clock uses changes in temperature to tell time. The clock was created by Che-Wei Wang and Taylor Levy, who are designers at CW&T, a multidisciplinary workplace that specializes in "architectural design, product design, custom electronics, custom software, robotics, and web programming/design."
The Thermochromic Clock works by taking nichrome wire and covering it in heat-sensitive black paint. When you add power to the wires, causing an electric current, they naturally heat up; this makes them transparent and therefore visible against the black screen of the clock. As the wires cool down, the numbers fade to black once again. To reset the clock, all you have to do is wipe down the screen with a cool cloth.