I picked up some IN-12B nixie tubes on ebay ages ago for no particular reason other than they’re pretty awesome! I had no way to run them as they require ~150 volts DC.
I came across the ArduiNIX shield, which has a built in boost circuit and dual output drivers allowing multiplexed control of 80 seperate elements which is enough for 8 tubes using the 0-9 elements or 7 tubes if using the decimal point.
The speedometer on my Opel Astra had taken to displaying random speeds a lot of the time and rather than replace the clock unit i decided it would easier, and more fun, to make some sort of display.
Being all electronic the clock unit only has one connector on the back with 36 pins which control all the gauges and warning lights.