This pendulum POV clock uses a Nixie tube to plot the time as it swings
Pendulum clocks are generally mechanical devices that time each second as it ticks away, but do little else. Jayzon Oeve’s concept, however, places the face itself – a single IN-12B Nixie tube – onto the end of a wooden pendulum. As it swings back and forth, four digits are progressively shown on the tube to create a unique POV display.
An Arduino Nano is the brains of the operation, along with an RTC module and an accelerometer that senses the pendulum’s position. When it’s straight up and down, an electromagnetic coil gives it a boost, keeping it ticking along “forever.”
You can see it in action below and find more info on the project’s write-up.