Last Supper

It's an interesting notion as raised by Wired in May 1999 (who said I was behind with my reading?) ... they were commenting on Da Vinci's Last Supper and that it has been restored so many times over the years that purists argue that it is no longer a Da Vinci. This reminds me of an axe at the Tower of London that Darien, a colleague at work talks about, that has had it's handle and head replaced so many times, it really is no longer the original, genuine article. I wonder how many important historical artifacts or relics are like this?