This is about stuff that could lead one into the rabbit hole of mad science. But it shouldn't.
What's the most efficient oscillator for its simplicity? How simple is the most efficient oscillator? How efficient is the most simple?
What's the most efficient "slayer exciter", and how inefficient is that? As a cordless charger / power transmitter?
Has anyone made a cordless charging pad like the Qi charger, but more flexible, with all the brains of the Qi charger, but capable of more?
Was there any power transmission device made from an inductive furnace, bulk tape eraser, or some such electromagnet device, good enough for the same thing to be made from scratch with nothing repurposed?
Six-ish questions that amount to one, you could answer one not asked and be answering, it's basically anything obscure relating to Tesla's final big plan. If he lived longer, wouldn't that be nice? Transistors, wow.