One of the greatest scams of the 1920s was that of Charles Ponzi of Boston, who promised investors massive returns on money invested. It wasn't a pyramid scheme, but rather a "Robbing from Peter to pay Paul" scheme, based upon using new money to pay off early investors with a large cut for Ponzi himself. The scam was exposed, people lost their money, and Ponzi went to prison. After he got out, Ponzi sold lots in the Florida real estate boom in the mid 1920s, which crashed spectacularly in 1926. From you tube, Patrick Boyle on Finance, about one hour, but well worth watching:
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