I were able to buy 300 Osram LG234TR Neon Glow Lamps very cheaply and I wanted to build a clock using them in a 7-Segment arrangement.
Before I started with this project I had no idea how to use a Raspberry Pi or write Python code. I hacked the code together after reading python tutorials for a few days and this is the result.
I used 228 of the Osram LG234TR Neon Glow Lamps. They have a built-in resistor and you can connect them directly to the mains. Power consumption is around 0,7 mA per bulb.
Each segment is connected to a separate relay which are controlled by a Raspberry Pi.

I bought:
1. Raspberry Pi 3B+
2. ModMyPi MCP23017 - 32 Channel I/O Expansion HAT to have enough outputs to control 29 relays
3. 4 8-Channel 5V Solid State Relay Boards
4. MEANWELL RS-35-5 5V/7A Power Supply to power the Raspberry Pi, the hat and the 4 relay boards (A 5A supply would have been more than enough)
5. 228 E10 bulb sockets
6. USB and HDMI expansion cables
7. a bunch of screws and washers

Solid state relay boards are more expensive than regular relay boards but I wanted silent operation and no relay clicks once per minute.