I love to watch "How it's made" videos like this one. It gave me inside in how piston rings for bigger ICE engines are made, and brought me the acrosstic that is featured on this page. Fortunately Youtube is awash with channels that feature videos about how every conceivable product is made, from a simple clothes pin to a high end telephone or exotic type of production machinery.
And then there are the very intriguing prototypes, that are handmade by craftsmen (and women), like this Stirling engine that fits on top of a pencil.