Spinning levitating cube magnets with bismuth
Two 1/8 inch cube neodymium magnets spin in mid air, suspended between 2 bismuth discs and pulled upwards by a large magnet above the construction. The magnets were set in motion before the film starts by blowing air against the edge. It takes almost 3 minutes to come to a stop, only due to air friction.
At the end of the movie the pulling magnet is wiggled a bit so you can see how steady the setup is once correctly installed.