Vanilla Minecraft gives you a furnace and a pickaxe. Modded Minecraft gives you a power grid.
On ownd.dk we play IndustrialCraft 2 and BuildCraft, two of the classic tech mods, on good old Java. You start by tapping rubber trees for resin. A few days later you're laying cable across the map, a quarry is quietly eating a hole in the world, and somebody has started talking about uranium.
That's the whole game. Build something that builds things for you. Then make it bigger. Then don't touch it.
Treetap
Tap rubber trees for sticky resin. Resin becomes rubber, and rubber insulates your cables.
Generator
Burns coal and makes EU, IC2's electricity. Every grid starts here.
Macerator
Crushes one ore into two crushed ore. Twice the iron. Instantly worth it.
Pipes and engines
BuildCraft's engine-driven wooden pipes pull items out and stone pipes carry them on. The base starts moving by itself.
Quarry
A yellow-and-black frame that digs a big square hole to bedrock all on its own. Bring chests.
Nuclear reactor
Ridiculous amounts of power. Ridiculous amounts of heat. Look, don't touch.