It's already well known that Michelangelo dabbled in art forgery. That's not disputed. For instance, there's his famous forgery of the Sleeping Cupid. However, Lynn Catterson of Columbia University thinks that a much more high-profile forgery should be attributed to him. She believes that Michelangelo forged The Laocoon, which has long been regarded as one of the most important pieces of ancient Greek sculpture in existence. She points out that Michelangelo was present when The Laocoon was unearthed in 1506. She has promised to provide further proof to back up her allegation at a lecture today, as well as in a book she's submitted for publication. (thanks to Jelena for the link)