Well myself I am doing it partly by being a game developer, partly by using free open source code aka by co-opting existing free open source games to serve as "clients" or "views into" my "metagame" in which they all play a part, and partly from trying to start as much as possible from economics/finance games.
For example in Freeciv, some of the "city improvements" that cities can build are the Market, the Bank, and the Stock Exchange. So I thought well lets start with that: lets get Markets, Banks, and Stock Exchanges working as free open source code, so that cryptocoin enthusiasts and asset-trading enthusiasts can "play" as soon as possible with the bonus that the enthusiasts of such games seldom care about actually having a character on a map who has to walk through a city to reach the market or bank or stock-market and who thus might be vulnerable in-transit to robbers and greedy corrupt city-guards and irate housewives emptying their nightsoil into the street on top of the heads of passers-by and other such glorious details Role Playing Game enthusiasts might enjoy but, rather, tend instead to just buy high and sell low anything they can turn a profit on, even if whatever it is cannot be used to slay dragons or robbers or irate housewives or even as a conveyance to convey them safely back and forth between their lodgings and the Market, Bank or Stock Exchange.
In other words, I hope we can start quite abstract, with traders trading the coins/currencies of various nations on exchanges without maybe much caring even which nation controls how many square miles of which planet, how many characters of what character-types live in which cities that nation has built or is building on that planet, or other such details that Role Playing Game players and/or Civilisation Game players or even Rogue-like MMO players might find more interesting than just plain raw currency-exchanges, asset-exchanges or even, maybe - though this might be where the various types of players could interact - actual in-game-object markets where players could use various currencies and assets to barter, buy or sell various in-game objects such as armour, swords, guns, spaceships, military units, units of settlers capable of founding cities. or whatever.
SInce money seems so often the stumbling-block, a game being basically a hole in the internet into which you throw money, hoping maybe someday some players might also chose to throw money, it seemed prudent to start off with the making of money first, then elaborate around that once there is enough money to elaborate around.
So hey, maybe we can start by having good reliable free open source code for Markets, Banks and Stock Exchanges making money first, then use that money to paint in the planets on which the cities in which those get built exist.
The top level wiki page for this metagame concept is at
http://devtome.com/doku.php?id=galactic_milieuSome stats on some of the currencies and assets are at
http://galaxies.mygamesonline.org/digitalisassets.html and if anyone knows how to fix the fact that the nice GNUplot plots that worked fine running GNUplot in Fedodra 17 don't work when created using the same scripts against the GNUplot that Ubuntu 14.04 provides, that would be awesome so we can get the pretty plots working again.
Afficonados of scamcoins and shitcoins might notice that although in the game currencies such as UKB, UNS, CDN and such are blockchain coins whose blockchains run over faster than light communications channels, here on Earth they are not operated as blockchains for the simple reason that securing a blockchain is insanely expensive. Thus those asset pages refer to the Digitalis Open Transactions Server, which was where we were running them until such time as an affordable means of securely running them as distributed systems became feasible here on
the planet known as Earth.
-MarkM-