* Water. There's an ocean nearby and the desalinization plant in Aqua Town will keep running as long as it's powered. No issue there.
As far as I can tell, that's it. All essentials to keeping a city running, but of course it's not a complete list of everything anyone could want. We still ship in metal; there are no mines here, and recycling only covers a fraction of demand. We're also mostly reliant on other worlds for entertainment. A city of half a million sounds like a lot, but… (3/4)
…We don't have the level of skills or talent that a planet of billions would. Luckily cross-world bandwidth is cheap, so we can keep bringing in books, movies, video games, and whatever else we want from places with more population than ours. I'm glad for the Polywood studios, but they're small-time compared to the kinds of globe-spanning industries I've seen in other worlds.
The official server of the City of Elseways.