here's another one!
last weekend i visited a friend in berlin. he told me his weirdest field recording story, and it's actually to good not to share.
so this is what happened to him:
he & his girlfriend were on the berlin subway when a guy entered the train, nervously looking around, holding something in his hand. this friend of mine identified it as a taser. somewhat scared, they changed to another car of that train and agreed to call for help. this guy with the taser looked too suspicious! so they dialed 110 (german equivalent for 911), and were told to stop the train in the next station using the emergency brake. they did as they have been told, and as the train stopped the driver approached them. while explaining the situation the policemen arrived.
(i'll skip the funny subplot on how the police crushed down two other people before finally getting to the guy with the taser...)
unfortunately, during the identification of the potential violent criminal, my friend was able to have a closer look to the would-be taser. it turned out to be a field recorder.
this poor guy in the train was simply trying to record urban noises, looking around nervously to identify possible unwanted noise-sources early.
however, the police told my friend that he acted absolute correct; better safe than sorry.