http://eddietree.github.io/polysonic/
http://www.peoplebehindthepixels.com/
(commentary)
https://www.facebook.com/video.php?v=10152460523862864
https://www.shadertoy.com/
http://glslsandbox.com/
http://webglplayground.net/
rendering worlds with two triangles
http://www.iquilezles.org/www/material/nvscene2008/rwwtt.pdf
http://www.iquilezles.org/www/material/nvscene2008/nvscene2008.htm
http://www.iquilezles.org/www/articles/distfunctions/distfunctions.htm
http://geisswerks.com/gpucaster/index.html
http://www.kevs3d.co.uk/dev/shaders/
http://www.geeks3d.com/20130524/building-worlds-with-distance-functions-in-glsl-raymarching-glslhacker-tutorial-opengl/