By David Leinweber (author of Nerds on Wall Street: Math, Machines and Wired Markets, John Wiley & Sons).

The upper panel is a simplified schematic of a synthetic collaterized debt obligation based on various sources who for some reason seem reluctant to have their original work further exposed. The lower panel, taken from an actual U.S. patent for a "User -Operated Amusement Apparatus for Kicking the User’s Buttocks" is a nonsimplified schematic of the effects of SCDOs on the world’s financial system.