The mechanisms of early computing devices --- the gears, levers, springs, cams --- somehow strikes me as more ingenious than modern silicon and software. That a

The mechanisms of early computing devices --- the gears, levers, springs, cams --- somehow strikes me as more ingenious than modern silicon and software. That all those moving parts worked well and fairly reliably is amazing to me. And to think of the development effort... No testing in VM that you can just start clean whenever you need to. Of course that's also why the basic bar and bail mechanism was used for three decades.