Re: @AC 06:29
Can't remember where I originally heard it, but someone involved in security recounted a tale of when they were in a train carriage with a woman who was conducting several transactions on the phone at standard mobile-phone volume. After one or two such calls, in which she was giving all sorts of personal details, account numbers, dates she would be travelling etc, he began to take down the information, and then texted her (on the number that everyone in the carriage now knew very well) all the information he had about her just based on what she was shouting to the world. Apparently, she stood up and very angrily asked who had been listening to her calls ... all the hands in the carriage went up. She then proceeded to rant about how it was rude to listen to other people's private conversations ...
(If anyone knows the original of this story, I don't think I've embellished it much. If I have, apologies.)