Actually, I have been working on this tangent in a fairly focused way for the past month, and I finally have an image I'm prepared to post.
This was produced in PhotoShop 7 with a Wacom Bamboo tablet. I only used the basic soft and hard brushes and the eraser tool. This is just a study, a sketch, but in the face I think I've managed to capture a real painterly quality.
I'll keep at it, and I hope the next post will have some colour in it. Cheers.