Nature News this week reports (https://web.archive.org/web/20120612090323/http://www.nature.com/news/2008/080312/full/452138a.html?) that
Seven US-educated scientists working at the Max Planck Society's institutes are facing criminal charges for impersonating a doctor.
This extremely embarrassing story is fortunately no longer possible. The German Kultusministerkonferenz decided on March 6 (https://web.archive.org/web/20120612090323/http://www.kmk.org/aktuell/pm080306c.htm?) (text in German) to allow U.S. PhDs to call themselves Dr. in Germany. Until this story evolved (https://web.archive.org/web/20120612090323/http://blogs.wsj.com/health/2008/03/07/who-are-you-calling-doctor/?), I didn't even know that this is an issue.