I could watch this for hours! (and might)
Falling LEGO Domino Infinity Loop

Inspired by Grand Davis’ previously posted linear LEGO domino machine, fellow LEGO builder JK Brickworks decided to finally finish the infinity loop LEGO domino track he’d put on the back burner, where all my own projects remain. The build consists of a ring of 64 dominos that fall, and as they fall a ramp train runs underneath the opposite side of the track, standing the dominos back up from below. To make sure things run smoothly, a Mindstorm EV3 monitors the speed of the falling dominos, and adjusts the speed of the train to match. What a marvel of engineering. Also: how I managed to reattach my rear bumper with only zip ties. But will it pass inspection? The two Lincolns in my pocket say hopefully.