The Piltdown Man skull is being taken out of storage this month and put on display at Britain's Natural History Museum, as part of the Pfizer Annual Science Forum. They're putting it on display in order to mark the 50th anniversary of the discovery of the fraud (I guess it's better to celebrate when they discovered the fraud, rather than when the fraud was first perpetrated). The Washington Post has a good, informative article about the history of Piltdown Man.