Today: The Cardiff Giant, a historical hoax that happens to be one of my favorites, if only for the insane amount of conspiring and planning it took to pull off.
So a tobacco farmer George Hull got into an argument with a Methodist about the plausibility of giants mentioned in the bible (Hull being an atheist). Inspired by the argument, he hired some men to dig out a large quantity of gypsum in Fort Dodge, Iowa (telling them that it was for a monument to Abraham Lincoln). He then later sent it out to another man (who he made swear to absolute secrecy) who carved it into the form of a ten foot tall petrified man. After having invested a few thousand dollars in this hoax, he and his cousin William Newell buried it at Newell's farm. A full year later, Newell hired men to dig in the spot where the "giant" was buried, telling them that he was having a well dug out.
After the giant was found, Newell charged people 25 cents, and then 50 cents, to look at it. He later sold it to David Hannum for $25,000, who in turn was offered $50,000 by P.T. Barnum. However, Hannum refused, prompting P.T. Barnum to create his own plaster giant, which he touted as real, and called Hannum's giant fake. In response to this claim, Hannum is quoted with the ironic statement, "There's a sucker born every minute."
Finally, in 1870, George Hull admitted that the giant was fake, though that did little to stop the petrified man/giant craze sweeping sideshows throughout the United States.