My girlfriend wanted a digital calendar on the kitchen wall; I made one with a 24" monitor, a Raspberry Pi and DAKboard.
I’m using Prometheus to monitor my home office and homelab, I figured it would be cool to have a stack light show the active warnings and alerts from Alertmanager. So I made a HAT (Hardware Attached on Top) for the Raspberry Pi to drive a five-colored stack light.
I made a simple HAT (Hardware Attached on Top) for the Raspberry Pi to read multiple DS18B20 temperature sensors — it was surprisingly easy. I used the measured temperatures to control a fan using Home Assistant.