This video from 2012 is making the rounds right now–with good reason. Drop whatever you’re doing, leave your desk, quit your job, and find a magnet and copper tube, because, wow. Look at this! It’s a _Matrix _time-freeze in your hands.
The video is showing a demonstration of Lenz’s law: the magnet induces a current in the tube, and that current creates a magnetic field that pushes against the falling magnet. Try it with a similar setup (neodymium magnets work well), and bam: you’ve got yourself a slowly falling magnet. This phenomenon actually has practical applications in industrial separation of recylables, look: