What are mesecons?

"Mesecons" is a (free) mod for the game minetest-c55 (minetest.net).
It's the counterpart of redstone in Minecraft.

It adds wire and multiple receptors and effectors, such as switches, solar panels, water turbines, ...
You can also create logic gates or even computers inside the game with this mod, thanks to microcontrollers and mesecon torches (=redstone torches).

Download Screenshots

Great resource for beginners
and advanced users: