Print 128 bits on a punch card and read it from the webcam.

The goal isn't to program a computer; it's to store highly sensitive data on a medium that won't get erased. Like a crypto wallet key or a master password.

The webcam is used to read the punchcard via another python script.

It's more robust than a USB storage, an old paper or something similar.

via https://korben.info/des-cartes-perforees-imprimees-en-3d-et-lues-par-une-webcam-parfait-pour-stocker-vos-mots-de-passe-a-vie.html

other source: https://hackaday.com/2026/05/16/21st-century-punch-cards-are-3d-printed-and-read-by-opencv/