Miniaturize a whole logic network into a single entity to save place (similar to factorissimo but for signals).
Mods introducing new content into the game.
Entities which interact with the circuit network.
I'll just put that here: https://www.youtube.com/watch?v=TCxIghf4Z_0
Factorio Forums post: https://forums.factorio.com/viewtopic.php?f=193&t=103850
