After adopting the euro, Greece borrowed huge sums of money. The country is now on the brink of a major default. "They're going to default ... it's now a question of how messy it will be," says writer Michael Lewis. His new book Boomerang looks at Greece and four other places affected by the financial crisis.

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Social Security has been compared to Ponzi schemes for decades, says Indiana Gov. Mitch Daniels. In his new book, he lays out ideas for improving the system. Mark Wilson/Getty Images hide caption

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More than half of Americans are at risk of not having enough money for basic expenses in retirement, experts say. iStockphoto.com hide caption

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A Greek pensioner burns his emergency tax bill during a protest Wednesday outside the Ministry of Finance in the center of Athens. Louisa Gouliamaki/AFP/Getty Images hide caption

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Job seekers participate in a career counseling session targeted to an over-50 demographic in the Harlem neighborhood of New York. Human resources professionals say there are fewer leadership positions available, so it may take middle-aged workers longer to find a good job. Chris Hondros/Getty Images hide caption

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Republican presidential candidate Herman Cain speaks in Orlando, Fla., on Saturday. He won a GOP straw poll there with 37 percent of the vote. Mark Wilson/Getty Images hide caption

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