https://www.instructables.com/This-High-Voltage-Click-Clack-Toy-Rocks/
This High Voltage Click-Clack Toy Rocks! : 11 Steps (with Pictures) - Instructables
This High Voltage Click-Clack Toy Rocks!: Here are two electrostatic versions of a retro Click-Clack toy that were popular in high schools back in '70s....
click clack toyhigh voltage