Deep Learning Factory Insects
I'm imagining a swarm of metal insects that build functioning 1st world cities that each run on a self-contained energy loop. They consume local resources and process them into construction materials. They even combine in large groups, mechanically, to become temporary factories to process materials, fabricate components, assemble components, and build the city as a single functioning unit that can provide shelter, heat, electricity, and even an automated system of good food and clean water to sustain 20 million people. This would include automated farming of everything from cows and chickens to apple trees and tomato vines, completely in a closed hydroponic environment. If even one small thing is broken, you can be sure there will be some DLFI flying in to make immediate repairs. Humans need not apply. Just enjoy.
"Link, Connect, Infinity Drive. Build an Iron Clanking Hive" -Claw:Mechos