Sorry for not replying earlier, you where the last person to post previously so I completely overlooked the tread.
Here is what I tend to do.
1-Desaturate the picture
2-Use curves to exaggerate contrast
-Tip 1. If you apply a blur and then use the curves you can round off corners.
--Tip2. Don't be afraid to change anything you not happy with,
if it looks really wrong at the moment its not going to get much
better. Better to clean up the picture now.
3 - Apply levels
For levels I would you something like
* 55 , 1 , 75
Give or take 5-10 depending on the picture for a comic like effect.
4- The most important bit.
Simplify. Smooth out sharp curves and remove unwanted lines. You will have to do this with more complicated pictures.
The are other ways of getting a similar if not the same effect.
*You can use the photoshop filters like Cut Out with a desaturated picture.
*You can always "trace" the image in Flash/Illustrator of a free alternative from the net. Paint.Net actually has the feature.
http://dsarchy.deviantart.com/
