Tangentially but our local small-town hospital ran its TV system through a C64 system for decades. It was there until the hospital was bulldozed and replaced around 5 years ago. I don't know exactly how it worked but my dad was the engineer at the hospital and explained it was used to provide TV services to paying (private insurance) patients.

All I recall is that whenever a TV was switched on you'd see the C64 load "*" prompt for a few seconds before the picture kicked in. This got me wondering about the guy who set that up, and a bit impressed with how it kept running without issue for so long, since as far as dad could recall they didn't need to do any maintenance on it.

I'm just imagining a dusty C64 forgotten in a crawlspace somewhere with a big "Do not turn off" label on it. I wonder what happened with it, I wouldn't mind seeing the code and setup. (edit - I've sent him an email to see if he recalls any details as he was there from the late 80s onward...)