wow...I wish I could do that. Really really dig the second image.
One of my halloween buddies does it. He usually dresses up as The Crow. When people come near, he rolls his eye up. Really creepy. One of my other buddies is blind in one eye. He usually wears glasses, but at halloween, he lets the bad eye out. He had Cancer when he was young, and lost the vision, but it really has a great effect, especially cause he dresses as Jason.