Comment by stavros

I've built tons of things. Most usefully, I built presence/motion/light/temperature sensors for my home, along with IR transmitter so I can control my TV/AC. They're about the size of two matchboxes, they cost about $10 each and they're amazing for my home automation:

https://gitlab.com/stavros/sensor-board/

I've built cat toys for my blind cat, toy planes, a CNC, a cat feeder, a back-scratching robot, and more stuff that I can't remember. I love the ESP8266.

Also, an e-ink display that shows my calendar:

https://www.stavros.io/posts/making-the-timeframe/

A house with a tiny person living in it:

https://www.youtube.com/watch?v=1RUqTN-7_gU

A way to project images in mid-air, for long exposure photography:

https://www.stavros.io/posts/behold-ledonardo/

A button that I can press to get food:

https://www.stavros.io/posts/emergency-food-button/

A drone that blows bubbles:

https://www.youtube.com/watch?v=xk99zrlAp9U

A toy bus that shows you when the next actual bus will come:

https://www.stavros.io/posts/bus-stop-bus/

A rotary mobile phone:

https://www.youtube.com/watch?v=fSkdWQswpc8

An alarm clock with the weather so I know whether it's worth waking up for tennis:

https://www.stavros.io/posts/do-not-be-alarmed-clock/