Numitrons are neat display devices similar to nixie tubes but designed for much lower voltages. Numitrons are basically incandescent displays in which filaments create the segments.
They have a retro look that i liked so much. I bought 6x IV-9 russian numitrons in ebay, they were about 3$ each, they're pretty cheap!
At that time i didn't know what to do with them, but then i thought about a clock. Using software from a single LED display clock i made this impressive numitron clock.