A rather effective argument for lisp (or at least s-expressions) as a structured language for storing data. Must find libraries to work this kind of functionality into Languages of Choice. (rather than use lisp of course. That would just be silly)

" ... We present a new low-cost optical design so that the tags can be shrunk to 3mm visible diameter, and unmodified ordinary cameras several meters away can be set up to decode the identity plus the relative distance and angle. The design exploits the bokeh effect of ordinary cameras lenses, which maps rays exiting from an out of focus scene point into a disk like blur on the camera sensor. This bokeh-code or Bokode is a barcode design with a simple lenslet over the pattern. ... " -- A very small alternative to 2d barcodes and RFID. May possibly work with reflective light

" ... Suddenly an idea flashed. It was simple, and elegant - conventional halftoning is based on little dots - which were usually ellipses of various sizes, oriented at a 45 degree angle (a subtlety based on the visual cortex's distribution of angle detectors... angled ellipses are less perceptually intrusive - except to certain African tribes that grow up in rounded architectures rather than Western Cartesian architected buildings). Digital halftoning aped analog halftoning, which was based on optical screens of repeated patterns - and all the little elliptical dots in a picture, such as a newspaper picture, always leaned in the same direction. My insight was under computer control this did not have to be true; you could make the little dot lean left to represent a zero, and to the right to represent a one - and that this would be essentially perceptially invisible ... "

Easy flow diagram leading to the right kind of data depending on what you wish to display about a particular data set.