In a similar vein – neon tubes. A plasma tube is a low-pressure tube filled with a noble gas and electrodes on opposite ends. It excites the gas but due to the low pressure if the voltage is large enough and the tuned frequency is relatively low, you would get something similar to lightning (without the high amperage).
Plasma tube
Got this gizmo from a garage sale – the owner thought the transformer was burned out. I had to replace the plug. What a find! This thing is fairly big – 24″. I’ll try and post a better picture. It’s mesmerizing…
-Uncle Mark