Charles Ponzi was an Italian swindler who is now famous for the financial fraud that bears his name. The original scheme used postage coupons, which were cheaper in other countries than in the United States. By buying coupons abroad, Ponzi could make a profit by selling them in the United States. However, that's not what made him famous. Rather than simply arbitraging the postage coupons, Ponzi found an even faster way to make money: he would attract investors with promises of outlandish profits, while actually using their money to repay old investors. The scheme worked until he ran out of gullible investors, and Ponzi was ultimately convicted of mail fraud.