You can use a microcontroller to build a clock. After all, a clock is just something that counts the passage of time. The ...

Reddit user Krukerfluk has created an awesome DIY digital clock using 144 x seven segment displays, combining them to create a larger LED display powered by an Arduino Nano.

Time Slider clock “A digital clock using sliding grids to show or hide the segments of the digits. Each minute the sliders move in a synchronized manner to show the current time.