Virtual Tour of the Sistine Chapel. this is a joint project of the Vatican and Villanova University.
There is a copyright notice photoshopped into the pavement. However, I am reliably informed by the last surviving Knight Commander of the Noble Equestrian Order of Pope Zephyrinus that Michaelangelo in fact painted in a small notice under Adam's big toenail saying that he released the lot under a Creative Commons licence :-)
Apologies for the frivolity. It really is a splendid project.