Thanks for the replies, guys!
I know I didn't describe the idea very well--that's because it's just an idea, so far. I made the 1966 versions in many forms, mostly in a routed-out Walnut board that would hang on the wall like a picture. I used
NE-2's, AR-2's, and ZE-2's (Zenon) for various colors.
Now, obviously LED's would be the choice, but the circuitry will be different, as the gas discharge lamps were part of the circuit.
They were purely decorative--just a random blinking patern, but they had a definite appeal. I can still get NE-2's, but they don't make the 45-volt batteries nymore.
I can use a simple half-wave rectifier on the house current for the supply, but then you have a cord to deal with.