A couple of years ago I built this prototype power supply for a large CO2 laser. The interesting thing about it is that it completely microcontroller driven and uses a rare series resonant topology. It deliveres up to 30KV and an adjustable constant current of up to 25mA.
After considering it lost I was pleased to find it again.
I was able to get it running and decided to show some fruits who is the boss...
As the picture from inside the power supply shows it is really simple consisting of only a few parts:
The power supply was originally inspired by this article