Here is my nixie clock :

6x IN14 russian tubes 6x Neopixels Leds 2x HV5530 high Voltage drivers 1x 210V High Voltage step up power supply 1x 5V step down power supply 1x ESP32 microcontroller 1x radar sensor 1x light sensor 1x (option) temperature + pression sensor 2x home made pcbs

And one Android application speaking to the ESP32 with Bluetooth Low Energy

Just add a piece of wood (from Vietnam :)) a CNC mill, a 3D printer (for spacers and leds' light under the tubes), one lathe (for aluminium rings) and a lot of hours.

see it in action here : https://www.youtube.com/watch?v=7I_mB28OVZ8