Well, I wanted to do it on any one of my people renders. I was thinking something along the lines of the look of "A Scanner Darkly". I found a couple of tutorials on it but my Illustrator skills stink.

This is the setup I came up with: live trace the image using the attached settings in Illustrator, then export the image back into Photoshop and use Poster Edges on it.

I tried it on this render here, tell me if you think it is on the right track.