Solenoids are common electromechanical devices. They're used in pinball machines to make the ball shoot away when they hit a bumper. If you've ever have the opportunity to touch an energized pinball bumper, you will immediately gain an appreciation for its explosive power. In this video, famous hardware hacker Jeri Ellsworth takes apart a pinball machine solenoid to show how it works. [via Hackaday] Image: Youtube screenshot