Maker Michael Klements has built a unique electromechanical clock using a little Arduino hardware, code, and 28 servos, ... The Arduino Uno reads the time from a DS1302 real-time clock (RTC) ...

You’d need an ESP8266 to run the clock code, or if you’d rather sit and admire the rainbow light show unabated by the passing of time, just use an Arduino Uno or something similar.

It comes as a kit with hardware plans, schematics, source code and instructions so you can make whatever adjustments you want. LED colors come in red or green. The only down side is the price ...