Monument to headier times: The euro logo outside the European Central Bank in Frankfurt. The International Monetary Fund has warned of possible deflation in parts of Europe. Frank Rumpenhorst/AFP/Getty Images hide caption toggle caption Frank Rumpenhorst/AFP/Getty Images Planet Money Wait, Investors Paid Germany To Hold Their Cash? July 19, 2012 Government debt auctions have been turned on their head in a few places recently, with investors promising to pay interest rather than receiving it. We examine what it might mean.