Leonardo’s Last Supper is pretty cool, even without Dan Brown’s conspiracy theories. One thing you notice in person that’s not as evident in most art apprecation and/or history textbooks is how badly it has deteriorated. Evidently Leonardo was experimenting with new techniques, and they evidently weren’t that great. (“Always aim high enough to fail?”)
This new website provides an interactive look at the Last Supper that includes really incredible amounts of detail, plus a cool background section. Check it out.