Other
Chinavista: The Great Wall, a Virtual Tour
This sight provides historical information as well as pictures on the Great Wall of China in an online virtual tour.
Other
Connected Globe: The Great Wall
A personal account of someone's visit to the Great Wall of China. Features great pictures of the wall.
NASA
Nasa: Great Wall of China From Space
Proof that you can see the Great Wall from space, but you can't see it from the moon.