A friend of mine had a pic done of
her that looked cel-shaded (or rotoscoped if you like) and i asked where/how it was done and she pointed me
here there's a tutorial on how to do it and i used it to a degree and used some of my own ideas/techniques to produce
my very own. Feel free to comment or suggest easier or better ways to get the same (or better results).
edit:
The original (scaled down) for comparison.