The clock is based on the AtMega328 and Arduino, it uses a home-brew RTC board that I hacked together using a DS1307. The code explores software-driven multiplexing, and supports two different intensity/brightness levels (the seconds are dimmer than the hours and minutes if you look closely).
The time for the DS1307 was configured/set out of the circuit using a Bus Pirate, then powered down to run off the backup coin cell, and inserted into the clock circuit.