Rainer Kohlberger's brilliant pxl app. There are other things that achieve similar effects, like Poly and Dmesh. With Poly you have to do some actual real work (although not much and it's fun); I'm going to try out Dmesh next. But pxl stands out because you can export your auto-processed artwork as a vectorised pdf file, which makes the results much more useful.
DMesh by Dofl Yun by firstborn. DMesh, designed by Firstborn's Dofl Yun, is a custom creative application that turns images into techy artwork. It works by analyzing an image and generating a triangulation pattern for a beautiful finished product.
DMesh I just tried a quite interesting software, DMesh (a triangulation image generator), and although the result doesn’t seem to take a huge advantage of its potential, it sure is something that you can create tons of great stuff. Try it here