> adding an application (not just a program binary) is as easy as extracting a package into a folder and integrates with the rest of the system
I have fond memories of installed Warlords Battle Cry 3, Warcraft 3, AOE2 etc. directories on flash drives, distributed to 20+ kids in high school (all using the same key). Good days.
Way off topic but you just reminded me of all the time I spent playing Warlords 3 (not Warlords Battlecry 3, the original Warlords games were turn-based). One cool feature it had that I'm surprised I haven't really seen other turn-based games do is a "play by email" option similar to correspondence chess, except you're just emailing save files back and forth and the game makes importing/exporting the save files via email a bit more streamlined.
PBEM was not uncommon in games from that era. The other title I can think of that had the same feature built-in was Age of Wonders.
Civilization V has a "cloud game" option that keeps the save file online. Players can then take their turn when they have a chance (though non-responsive players can break the game), and if you're running the game through Steam you'll even get a Steam notification when it's your turn. You can also define a webhook that gets called when it's somebody's turn. One of these days I'll put together a little tool that takes that webhook message and translates into a Discord PM or Discord channel post @-ing the person whose turn it is.
They specifically say that it's their way of paying tribute to Civ playing by email.