The various development boards such as the NodeMCU or Wemos D1 make working with the ESP8266 an absolute breeze. If they have a downside, it is that they are larger than the bare ESP2866, and of co… ...

This is the SB116, an 8-bit programmer’s calculator powered by an Arduino Nano. It features a 128 x 64 pixel monochrome OLED display and can be powered by either a USB port or three AAA batteries.