I'd guess the limits of information theory have been just about reached. The only real improvement I can think of would be either the ability to scan and resol

I'd guess the limits of information theory have been just about reached. The only real improvement I can think of would be either the ability to scan and resolve smaller individual squares (and that is dependent on how much the printer ink bleeds), or printing in color. It would be cool to update optar, and make it a little more flexible. It would be fun to make a python package that can output arbitrary data as a printable image.