The brick wall by my back door has been bugging me for years, so I built a control panel to mount on it. Gauges, a clock, some switches for the gate and garage door, a little screen showing temps from around the house. All of it actually works, no fake gauges. What I did not expect was how deep the rabbit hole went. I thought I'd knock it out in a weekend. Instead I spent whole evenings just on the dial faces, aging them with tea stains so they didn't look like laser prints. Then the switches needed the right throw weight or the whole thing felt cheap. Then the wiring behind the panel needed rework because I'd routed the 24V thermostat lines right next to the speaker wires and got a hum in the audio.
The last detail that nearly broke me was the handset. Found an old corded phone at a flea market and spent two nights figuring out how to make it ring when someone hits the doorbell button. Got there in the end though. Now when the gate opens from the wall panel it feels like launching a submarine, and honestly that's the whole point.