This Arduino Sketch controls a NIXIE clock with 4 tubes. 
I used a plain ATMega168 microcontroller instead of an Arduino board for obvious reasons.
Here is a picture of the circuit board: https://github.com/fiendie/NixieClock/raw/master/images/circuit.jpg

I am using a DS1307 RTC chip to keep track of the time. 

The schematics can be found here: https://github.com/fiendie/NixieClock/tree/master/schematics