I've made a nixie clock.
It uses four IN-12s number nixies, one IN-35 bulb, four 74141 nixie drivers, two 595 shift registers, four 22k ohm resisters on the nixie anodes and a 200k ohm on the bulb. The nixies are driven by a 12v - 180v unit, the clock is a DS1307 (with battery backup).
The circuitry is currently all on a breadboard, I use a PC PSU for power (you may notice the arduino is powered by usb, this is the board I set fire to when I had a short and now only powers from usb. I knocked up a molex-USB cable). The nixies are suspended from a Meccano gantry, and the arduino is attached to the side of it.
Front view (using a flash):
Every now and again it displays a load of random numbers. The amount and duration of the numbers is random, the interval between episodes is random (but a maximum of about once every 2 1/2 minutes - though it's currently shorter for the purpose of shooting the video). This is to give it a bit of a faux flakey technology feel, I may add a small buzzer to increase the effect.
Tomorrow I'll be putting it in a box tomorrow, including dumping the big PSU since the 180v PSU has a 5v output.
sorry about the quality of the video...