Who said that single LED projects are boring? IoT Iron Man notification system.
What's scarier than a pair of Uncanny Eyes? Five pairs of Uncanny Eyes mounted on skulls and controllable to make everyone scream.
Make a simple weather station using an ESP8266. You can also use the ESP32 or Raspberry Pi too.
I built a scale from an old one I had laying around. It works with Android notifications and logs your weight to Google Fit.
