In the past few years, we have covered plenty of cool Nixie gadgets that you can buy. You can always build your own if you are comfortable with electronics. This video from Sideburn Studios can give you a few ideas. It shows a Nixie Tube Robot sculpture that plays random sounds and blinks.
The NixieBot has two Nixie tubes embedded in its forehead. It runs for up to 2 hours on battery. The robot makes random machine sounds.