When I was young, I had an electronics mentor name Mike McNatt that was an EE from OSU. He taught me a lot about electronics and hired me to work at his computer consultancy firm while I was still in school. He did a lot for me, helping me get an 1802-based computer that I could program in machine code. He later helped me get a much improved computer based on the 6502, very much like the Apple II.
But the funniest thing was that on my birthday one year, he gave me an ST shouldered tube like a 2A3 with an integrated circuit super-glued on the anode lead on top. It had a caption that read "Microprocessor Controlled Tube". That was the funniest thing to me then. Even funnier to me is the realization that CD players driving tube amplifiers today is actually the very same thing. Who'd have thought it?