A set of cheap temperature sensors out of D1 minis that report data over MQTT. Just a simple piece of code, not using any fancy stuff like ESPHome or Tasmota as there was no need for it. In the end they are supposed to guide the gas boiler heating over OpenTherm, but haven't done that part yet.
I've also made an e-ink calendar with bin collection schedule with Inkplate (ESP32) [0] and now I'm making a Frets on Fire-compatible rhythm game based on ESP32-S3 [1] (initially made for the CCCamp's flow3r badge, now designing a simplified board for it [2][3])