More than 1 million people in Peru earn less than the equivalent of about $450 each year. Courtesy of Michael Rizzo/CGAP hide caption

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Customers wait to collect money at the Juba Express money transfer company in Mogadishu, Somalia, on Feb. 12. Mohamed Abdiwahab/AFP/Getty Images hide caption

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Supporters cheer in Colorado Springs, Colo., as a television broadcast declares that Republicans have taken control of the Senate. Republican candidates, party committees and outside groups spent about $44 million more than Democrats, according to the Center for Responsive Politics. Marc Piscotty/Getty Images hide caption

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The next generation of Australian dollar notes will include tactile features to help people with visual impairments differentiate between them, says the Reserve Bank of Australia. Last year, the agency met with a boy who started a petition asking for the change. Torsten Blackwood/AFP/Getty Images hide caption

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While people can often estimate how much they might need for 10 or 15 years of retirement, that calculation becomes more difficult for retirement that could last 20 years or more. Gary Waters/Ikon Images/Getty Images hide caption

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A money changer sits behind piles of banknotes in Hargeisa in Somaliland, an autonomous, relatively peaceful region in northern Somalia. The self-declared nation of Somaliland, like Somalia itself, lacks a formal banking system, and residents rely on hawaladars to receive money from abroad. Simon Maina/AFP/Getty Images hide caption

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Even some euro bank notes may need a good scrubbing. Like dollar bills, these notes are made from cotton and they harbor an array of bacteria. Thomas Leuthard/The Preiser Project/Flickr hide caption

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Several Silicon Valley entrepreneurs are developing services that manage consumers' investment portfolios with algorithms rather than people. iStockphoto hide caption

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An image depicts the SatoshiDice website, which exclusively uses Bitcoin, not dollars, for gambling. NPR hide caption

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The GasBuddy app and website rely on crowdsourcing — people across the country sending in gas prices. NPR hide caption

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