I like all his videos, but I particularly like this one because it kind of feels like the "missing link" between clockwork machines and electronic machines that I didn't realize I was missing a ton of stuff about.
Seriously, this guy makes great videos. I've enjoyed his videos on heat exchangers, VHS vs Beta, liquid dish detergent vs pods, or humidifiers way more than is reasonable.
Many pipe organs from the mid to late 1900's use similar electro mechanical technology to take the key presses and actuate valves in the organ closet to activate the correct pipe. I'd love to see him do a video on pipe organs, they're amazingly complex!