Got a new one for you which I guarantee is true. Back in the mid 1970s a Lufthansa 737 had a special logo applied with a large number 250 (or similar) on the fuselage to commemorate the 250th (or so) anniversary of something or other which was a big deal in Germany at the time (I am sure someone can fill in the right number but it is not important). On Heathrow Ground a curious controller asked, "Lufthansa 232 what does the big number on the side of the aircraft signify?". Before Lufthansa could respond the pilot of another aircraft using a strong 'mock German' accent replied, "Schpittfiers". Lufthansa 232 remained silent!