A friend joked about making accounts for their dog on self hosted services, so that it could turn lights on and off. What are some unconventional things you've seen for pets and homelabs?

Could just use a regular DC motor and limit switches.

My dog authenticates access to back yard with a Yubark Key that works over the wireless audio network.

It is a DIY setup. Basically is a sink bowl with the logic of a sump pump with high/low floats (couple of relays and sensors), a fountain pump to drain to a nearby sink, and a valve to fill. The timer drains the water every hour and the fill part is essentially a cheap shower head aimed at an angle so when it is draining and filling at the same time the water is swirling, making it (mostly) self-cleaning. I wipe the inside and outside every week or so just to make sure it is working and isn't growing anything.

Biggest worry since it is DIY is that something will fail and flood my house. I have a separate high level sensor that closes the valve, starts the pump, and sounds an alarm to help with that, and one of those cheap, warbling 9v water sensors nearby just in case.

I would also like to know this, best I could come up with was one of those electric water cooler pumps that fit over the top of the bottle.

It is a DIY setup. We had one of those bottle setups like you describe. For my big dogs all it did was slowly become more slobber than water. I realized the problem wasn't more water but getting rid of the slobber.

Post above describes what I did if you're interested.