Hand-run printing presses like these in 1909 produced 45 sheets an hour, while today's automated machines churn out 10,000 in the same amount of time. "This was considered the toughest job at the time," said Franklin Noll, a historical consultant at the U.S. Bureau of Engraving and Printing. "You had to work as fast as you could all the time on a rate where you only got paid for the good sheets." Library of Congress hide caption

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When the Swiss franc hit a historic high of buying .70 euros in May 2010, people lined up at a Geneva exchange office to get rid of their euros. This week, one Swiss franc bought .90 euros. Fabrice Coffrini/AFP/Getty Images hide caption

itoggle caption Fabrice Coffrini/AFP/Getty Images

When Canada switched to dollar coins, or "loonies," its simply took the country's dollar notes out of circulation. The GAO says the U.S. needs a similar plan. Ryan Remiorz/AP hide caption

itoggle caption Ryan Remiorz/AP