Show HN: PunchCard Key Backup

Summary

pckb -- PunchCard Key Backup About This small project -- available live at https://volution.ro/pckb (or https://purl.org/999 for long term permanence) -- allows one to take any 128 bits of information, and easily create (and especially easily recover) a backup of it into a physical medium, by using the old and tried method of punched cards (hence the project's name). For example, the 128 bit number represented in hexadecimal as d74ae47dc6f599d3f9cb847bd77d6b7c , can be backed up as the following standard (CR80 ID) card sized aluminium sheet, which can then be put into a safe place: All of this can be achieved by anyone at home, with access only to the following: using the self-contained HTML at the link above (https://volution.ro/pckb), either by entering the data manually, or by generating random data, one can get the hole punching pattern; (this whole procedure is described in the help, and you could consult it for more details;) from the same link above, or from here, one can print a standard (CR80 ID) card sized stencil, to be used as a guide for the hole punching; a small sheet of aluminium; (I've used a 0.5mm thick one I've bought from the hardware store for ~4 EUR;) a punch tool, used to mark (with the help of the stencil) where the holes should be punched; a small drill, used to actually punch the holes; (I've used a 1.00mm drill bit adapted to a standard screwdriver;) a cutter, to cut the aluminium steel sheet to the standard (CR80 ID) card size; (I've just used a ruler, and passed the cutter multiple times over the aluminium sheet, and in the end, it passed through;) (obviously, one can just use a wood plank, nail, and rock;) :) The recovery is as simple as: use the same self-contained HTML at the link above; make sure the checkboxes follow the punched holes pattern (for the key); check that the CRC checkboxes match the punched holes pattern (for the CRC); recover the base 10, hexadecimal, or text representation of the backendup information; Alternatively,...