Mohammed Morsi, the Muslim Brotherhood's presidential candidate, was the leading vote getter in Egypt's presidential election last week. But he did not get an outright majority and will face a run-off on June 16-17 against a former prime minister. He's shown here during a campaign rally. Fredrik Persson/AP hide caption

itoggle caption Fredrik Persson/AP

After hyperinflation in 2008, Zimbabwe abandoned its own currency, which included notes of 50 billion Zimbabwe dollars and even trillion-dollar notes. The main currency is the U.S. dollar, though the South African rand (on right) is also used in some places. Kate Holt/Bloomberg via Getty Images hide caption

itoggle caption Kate Holt/Bloomberg via Getty Images

An Egyptian woman walks under a campaign banner in Cairo on Tuesday. Egypt holds its first competitive presidential election on Wednesday and Thursday, with a dozen candidates in the race. Amr Nabil/AP hide caption

itoggle caption Amr Nabil/AP

Mohammed Morsi, the Muslim Brotherhood's presidential candidate, appears at a rally in Cairo. Morsi is one of 12 candidates in this week's election and has the full backing of the powerful Islamist group. Fredrik Persson/AP hide caption

itoggle caption Fredrik Persson/AP