Frédéric Bourdin is the Frenchman recently profiled in the New Yorker for spending much of his adult life impersonating "abused and abandoned children." He's spent time in institutions, posing as a teenager, and in jail; his biggest trick yet was convincing a Texas family whose child had disappeared that he was their long-lost son. He's said to be reformed, married and a father, but who knows. Here's his bizarre YouTube page, where he posts numerous videos of himself, including this one in the bath.

From the New Yorker article:

In October, 1997, Bourdin told me, he was at a youth home in Linares, Spain. A child-welfare judge who was handling his case had given him twenty-four hours to prove that he was a teen-ager; otherwise, she would take his fingerprints, which were on file with Interpol. Bourdin knew that, as an adult with a criminal record, he would likely face prison. He had already tried to run away once and was caught, and the staff was keeping an eye on his whereabouts. And so he did something that both stretched the bounds of credulity and threatened to transform him into the kind of "monster" that he had insisted he never wanted to become. Rather than invent an identity, he stole one. He assumed the persona of a missing sixteen-year-old boy from Texas. Bourdin, now twenty-three, not only had to convince the authorities that he was an American child; he had to convince the missing boy's family.