I'm also thinking of using the technology to program a paratrooper turtle that, when given a coordinate, will go off and build a small fort then come back... Actually I have also set up an automation facility that involves a turtle mining cobble from a generator, and from there all sorts of other things are produced:
Cobble
-> Smooth stone (smelting)
-> Stone bricks (crafting)
-> Sand (macerating)
- > Glass (smelting)
- > Glass panes (crafting)
So I have a few different things to make a fort from just out of automation. I guess I can make a tree farm work and add wood for chests and doors.
Anyway the point is I could build a facility that deploys turtles to random locations to build forts automatically. With a little bit of procedural generation I could even make each fort slightly unique. Leave it running while I go off and explore and start finding all these structures everywhere!
Turtles themselves are pretty easy to make. Most of the things you need can be automated, and red stone isn't too rare, at a rate of 1 per turtle. Swords might be a little tricky, as they require diamond, but it might be possible. It might actually be possible to not only have a large, menacing machine that deploys forts across the land, but also sends armed turtles to guard those forts!