I needed a presence sensor for my home office, so I took a Gonk Droid model from Printables, hollowed it out using negative modifiers in PrusaSlicer and then spent waaaay too long painting and grunging it up I also manually wrapped wires around the legs to give it a bit more visual interest. Inside is a Pico W, a mmWave sensor and some LED's - it communicates with my home automation server running Home Assistant (using MQTT) and controls the lights in my office.