Slightly related, one of the neatest desk toys that I’ve ever seen is a “perpetual motion” pendulum that has a hidden electromagnet. It bounces around playfully

Slightly related, one of the neatest desk toys that I’ve ever seen is a “perpetual motion” pendulum that has a hidden electromagnet. It bounces around playfully on your desk for weeks at a time. Was a great b-day present to my father. Also on the topic of patents, the one for this toy expired a few years ago and the circuitry is quite easy and a fun DIY project. Not my video but here is one in action: https://youtu.be/RUDTr99JClY https://youtu.be/RUDTr99JClY