How can I get a glow on where the light and shadows intersect? Check this video at 0:10
http://www.youtube.com/watch?v=rX3GaKJ71TE&list=UUrs4LpIdWbcg8mb_TVQewqg
Notice how on the wall, the red brick part on the left is causing the intersection with light to glow red and the yellow part of the wall on the right is causing the intersection to glow yellow.
I don’t think this is just a simple global glow post process (is it?)