I find it interesting that while all the electrical wiring in my home is typical AC at home-use voltages, the very first thing that almost everything plugged into it does is concert it to DC. I wonder if it would be feasible/logical/more efficient to have just one AC-to-DC converter per house, and distribute DC throughout the house (in addition to the couple places where things actually want AC), with a different connector and standardized voltage (9V?) and so forth.
It could probably never happen since everything needs to be backwards-compatible for people to use it. It’s just bizarre when I look around me and everything that’s plugged into the wall actually wants DC and needs to convert it first.