Walter Anderson doesn't have the same cachet as other names on this list, but he makes up for it with the sheer scope of his crime. A telecommunications entrepreneur, Anderson strung together an elaborate network of offshore companies and aliases to hide money. The result? More than $200 million in taxes owed to the Federal Government and the District of Columbia. To date, it's the largest tax-evasion scheme ever, and in 2005, it all came crashing down. Anderson pleaded guilty and was ordered to pay nearly $400 million after penalties and fees.