> most stable form of digital storage? Well, if you're asking literally, then probably cuneiform clay tables (fired on purpose, of course). However, a higher d

> most stable form of digital storage? Well, if you're asking literally, then probably cuneiform clay tables (fired on purpose, of course). However, a higher density medium with a reasonable lifetime would probably be a 2D barcode engraved on a plate of stainless steel or something like that. The ultimate of course would be 3D storage in synthetic quartz, but as a DIY solution, that is much more difficult to write (you need a short pulse laser for that), or even to read (for 2D barcode, any camera works).