Thea video feedback emulator offers a vague memory of fooling with video cameras and a strong flavor of crisp and fractal generative art, The results lurk somewhere between the decades. Click and drag your results for wild (and often brightly-flickering) variations. The creator explains how it works. [via Github]
What we've found most interesting about video feedback is: the sheer complexity of the images it produces through such simply-defined and implemented spacemaps that really only have to do with the relative positioning of two rectangles. It's somewhat intuitive, but always surprising.
This is all just scratching the surface of the mathematics behind the patterns that video feedback is capable of, but hopefully it's good enough for a start!
P.S. You'll notice that many of the "interesting" patterns contain regions of diverse sizes. That is, they appear to have a broad range of spatial frequencies. What's up with that?