I once met a chap who had done programming with a hand drill....
Ancient mainframe controlling a steel plant, booted from a paper tape that had decades before been replaced with a leather strap. He need to alter something in the boot process - so had to resort to a hand drill :-)
Steel cables connected between a mechanical signal and a lever, including fail-safes should cables break.
A special baton to carry, only a train carrying a baton is allowed to move.
These are still in use in some places.