This lead shot was taken early in the morning during Carnaval in 2008. From the shadows on the street, you can see that the light was coming from camera right, almost perpendicular to the line of sight. Had she been facing me, half the face would have been in shadow and half would be fully illuminated. But by waiting for her to turn into the sun, I got full illumination on the front of her face, accentuating her strong facial features.
So remember that whenever possible, have your main light illuminate our subject's face straight on. As I said, the Nose Knows!