This concept dates from my years in engineering school : while visiting an innovation fair, I discussed with two design students who wanted to create a more ecological printer. They had a laser-cut chassis, but not the printing mechanism. Remembering a recent NASA presentation for a iodine-fueled ion propulsion system for cubesat*, I proposed a printer based on it and a microplasma discharge reactor seen at a nearby lab.

I really like to solve someone's engineering problems on the fly using just my head, but I rarely have the occasion to do it unfortunately.

* https://www.nasa.gov/sites/default/.....ter_tagged.pdf