More on MainStreet From Scam Busters: The 7 Greatest Ponzi Schemes: 7. Charles Ponzi While Madoff has a punnier name (because he "made off" with his victims' money) this charismatic Italian immigrant gave the scheme its moniker. In 1920 he promised investors a 50% return in 45 days. Ponzi's plan was to buy postal reply coupons cheap from Europe and then exchange them for more than twice as much in the U.S. Instead, he paid his investors off with the new money that came in, about $15 million in nine months. Ponzi was exposed by a former Boston Post reporter he had hired for public relations. He was convicted of mail fraud and after being released from prison, was deported back to Italy in 1934. The Loot: $15 million (about $154 million in today's dollars) Read the full version of Scam Busters: The 7 Greatest Ponzi Schemes (on MainStreet). From Cramer: On Golden Ponzi: Madoff Scheme Akin to Social Security: Like Madoff's investors, Social Security's balance sheet is basically off the books, and Congress, playing the Madoff role, is using the Social Security fund as an ATM to fund pet projects, pay for earmarks, and cash in on boondoggles. And like Madoff, the last in will be among the first out of luck with Social Security. With more recipients and fewer contributors, Social Security is a Ponzi scheme that is headed for the same fate that has leveled Madoff investors. The Social Security's own 2007 trustee's report says that the fund could run out of money by 2042, and maybe sooner. Read the full version of Cramer: On Golden Ponzi: Madoff Scheme Akin to Social Security (on MainStreet). From Your Investment Fraud Questions Answered: Q: What regulations exist to protect investors?A: Securities laws guard against anyone making false representations to investors in connection with a stock sale. Criminal laws prohibit fraud. Investors also can file civil suits. Once an investor gets to this point, though, the battle may already have been lost. "Ultimately the best protection is to scrutinize any (investment) offer, because if it seems to be too good to be true it usually is," said Michael Budwick, an attorney with Meland Russin & Budwick in Miami. "Most of the protections come in after the investor has lost all his money." Read the full version of Your Investment Fraud Questions Answered (on MainStreet).