According to some science hippies, no known printing process based on ink could possibly produce an image that small, but what do they know?
See, the trick is to manipulate a set of ten single aluminum atoms (which is roughly the correct size) to present their electrons primarily on a single plane which sorta gives the effect of a bee flapping its wings.
Developing this technology would be a good use of time and definitely have unforeseen benefits for humanity.
The one place where we've perfected this technique is on Valkyrie's Choice. It's not apparent on every can without an electron microscope, but if you buy a whole case (and an electron microscope) you should be able to see it on at least one can.