I think this all the time. Try going in pitch black with a picher of water, a flashlight, and a bowl. As you pour the water in to the bowl shine the flashlight across the water. It will move sightly with the light.
If the Avengers were cats, Tony would totally be a sleek Siamese in purrfectly tailored armor. And the Hulk would definitely be a big fluffy Persian - or a Maine Coon. <<<< And they wouldn't be the Avengers. They'd be the Aveng-purrs.