Remember "Thieves World"? It was a game supplement (a superbly detailed city) by Chaosium, based on a line of fiction anthologies set in that city, written by multiple authors and curated/edited by Robert Asprin.
I am thinking of putting together a team of writers/designers to create a future city supplement along those lines (working title: "Ubiquicity"). I was going to do it myself but the future is hard to predict in toto, and I think this can be a much better product if it's multi-valent.