Leonardo da Vinci's priceless masterpiece, the Mona Lisa, and her perplexing smile, has fascinated art lovers and historians for centuries. But who was she? One man in Italy is attempting to find out. CNN’s Ben Wedeman has the story. “In the frigid bowels of what was once a convent in Florence, television producer-turned art researcher … Continue reading Have they found Mona Lisa? Art researcher searches to identify model's remains; Ben Wedeman follows the trail