- 4 digits that need to be driven dynamically from ESP8266 - considering that digits are driven using a 595 and it all runs under MicroPython, it's kinda slow
- 5V input and onboard 3.3V regulator (Chinese 1117) - which can be bypassed by a solder jumper
- GP2, GP0, TXD, RXD and ADC pins are free and accessible (okay, TXD and RXD are not very accessible) (also, it appears that GP0 can't drive open-collector things, IIRC because it has a pulldown)
- Lying on the hackerspace floor, broadcasting poop emoji SSID and displaying "1337"
- Showing temperature from two temperature sensors (still broadcasting the poop emoji SSID)
Things to play with: