I occasionally waste a bit of my time hunting for surprises deep in the Mandelbrot set. To that end I wrote a simplistic program that enables unlimited zooming with arbitrary precision arithmetic. Would you have guessed that there are strangely smooth curves and 90 degree angles very deep down there?
These stars really are a meta shape; i.e. they arise not so much naturally from the fractal's formula, but can be found almost everywhere if you zoom deep enough and do so very selectively. Around 500 bits of precision were needed for the examples above, and roughly a week of processor time each for the large, anti-aliased versions. Multicore machines to the rescue! :-)
The colours have not been chosen for artistic value, but mostly for (de-)emphasis of certain structures in the image. To that end, each of the three images is misleading in one way or another. The star shapes are not always as prominent as they appear here.