Adruino based micro running custom code. Using the FastLED library to drive the WS2812 LEDS ( aka neopixels)
Started with a wood base to prototype. Moved to acrylic as soon as the dimensions worked out.
2 button Interface. Press one to adjust hours. Press the other to adjust minutes . Press both to change the color scheme.
The LEDs are the 4 part, 60-led ring available from Adafruit (about $US40 pre ring) or on ebay for less.
Every hour, on the hour, it does one fast colorwipe per hour as a form of digital cuckoo.