I am by profession a programmer. My main hobby is 3D modelling/printing, other hobbies include electronics, mechanics, etc.
The idea was to add more GPIOs and analog inputs to the ESP8266. It was achieved with SPI. The additional I/O pins are usable via native Arduino calls. More info about this project here: https://github.com/Hubberthus/ESPExtra/wiki
After accidentally breaking my custom module's LCD screen, I've decided to buy a RepRap graphic LCD module, and create an adapter for it which also includes cooling fan PWM control.
This printer has Sanguinololu board, which unfortunately does not have standard expansion ports, so I've decided to build an LCD+SD module myself, with a connector just right for Sanguinololu. Success. Then accidentally broke the LCD screen.