This is just messing around with a technique to try and make it look a bit more like a comic book drawing. The effect is done in this manner:
1) Duplicate the image
2) Greyscale it
3) Duplicate the greyscale image, set it to dodge, and invert the colors.
4) Use a Gaussian blur (4 or higher should do it) on the inverted selection. Now you've a pencil sketch sort of image.
5) Merge down to get the "sketch" on one layer. Set it to burn.
6) Duplicate the burn layer a few times until you get the look you want. I think this was 4-5 burn layers stacked on top of one another.