It is always handy to have few digital thermometers around the house. You may want continuously monitor indoor and outdoor temperatures, Use it for specific needs, for instance when preparing food or regulating boiler water temperature. If you would like to check digital thermometer value from a distance, then you should go with bright display. You can always use large bright LED seven segment displays, but if you have few spare nixie tubes around, why not use them instead.
Luca Dentella have build three digit Nixie tube digital thermometer based on Arduino. He has chosen 10K thermistor based temperature sensor which can be easily read through Arduino analog input. He wanted nixies to look even cooler, so he added RGB LEDs with WS2812 control chips underneath each tube. This way he could get cool effects by adjusting background color according to temperature values. Lately he completed his project by assembling thermometer on PCB he received. Only one thing that is still missing is enclosure.