No small degree of turmoil was unleashed in the currency trading community yesterday when it became known that Benjamin Lawsky, superintendent of the New York State Department of Financial Services, requested documents from more than 12 banks pertaining to their currency trading practices. According to Bloomberg News, the banks include Goldman Sachs, Deutsche Bank, Credit Suisse, Citigroup, and others. It seems likely that one result of the investigation is that any currency traders who are left at the end of it will be reduced to communicating via carrier pigeon.