OP said SINCE the lightbulb - it is acknowledged that the lightbulb had more effect :) As you say, it fundamentally changed almost everything. It made it possib

OP said SINCE the lightbulb - it is acknowledged that the lightbulb had more effect :) As you say, it fundamentally changed almost everything. It made it possible to safely, reliably put light where before there was no light. The light of burning things is, by comparison to electric light, horrifically dangerous, expensive, unreliabe and inconsistent. Electric light not only enabled people to do things in the hours of darkness, but to create new places to work in, or just to store things, or to create new objects and mechanisms using the new ability to put light anywhere we wanted whenever we wanted (could you imagine trying to inspect the interior of some complex internal component of some huge fantastic construction using a gaslight, or a lump of burning wood?). The tiny bulb in a torch (US - flashlight) is so ubiquitous, but so incredibly useful. So many industries suddenly became so much better, so much safer. Mining, transportation. Lightbulbs touched everything, and created not just new ways of doing things, but made the impossible possible. So far, the internet and cell phones have not been nearly so revolutionary, but the OP did say "since" :)