Vladimir Brajovic is a robotics researcher at Carnegie Mellon University. His goal is to give a better vision sense to robots. But in an unexpected side-effect, he developed a smart system to automatically enhance underexposed photos. The result, the Shadow Illuminator, is quite convincing.
Shadow Illuminator examines the content of a photograph, estimates the illumination conditions and then brightens shadows. It also enhances details within the shadow. You can upload your pictures on the free website and see how they can be enhanced.
This picture was run through the free service at http://www.shadowilluminator.org/
Pretty amazing, no?