I did something similar a few years back. Basically converted binary data to a matrix and printed it max res (1200dpi inkjet), also wrote the software to read i

I did something similar a few years back. Basically converted binary data to a matrix and printed it max res (1200dpi inkjet), also wrote the software to read it like a QR code (with perspective & error correction etc). You can easily save several MB per page. The theoretical number is much much higher for color printing, but is gets very complicated (inkjects are basically stochastic with regards to dots, YMCK balance is finicky etc). Also some time after that project I noticed that some gov agencies use printed "QR" codes to send sensitive data (ie biometrics) from office to office in the traditional mail format. It works, but so do floppy disks and nobody's using them anymore for a reason. It was a cool project though.