International reply coupons

Most investors have heard about "Ponzi schemes". These are the name for investment scams where promises are made and new investors' money is used to pay old investors. Eventually, the scheme collapses when new money slows. Surprisingly, the basis for Ponzi's scheme still exists. Ponzi bought IRCs (international reply coupons) in low-cost countries and sold them in high-cost countries. It's a valid arbitrage. IRCs can be exchanged at post offices for international postage. http://www.upu.int/en/activities/international-reply-coupons/about-irc.html Unfortunately for Ponzi's victims, while buying and selling IRCs could theoretically be profitable, there were several problems. First, the market for IRCs is small. After all, making only a few cents per IRC requires many millions to be traded before a large firm gets profitable. Second, in addition to the overhead of buying and selling coupons there is a large cost to shipping and handling all those coupons. Finally, the biggest problem was that Ponzi was an outright crook. He wasn't really buying the IRCs, he only took in investor's money and claimed he was trading IRCs.