Don't believe a word about the world-weary, cynical ways of Londoners. When an independent research company this week approached 200 random people on the gold-paved streets of the capitol, 60 percent of them were prepared to divulge their PC's password. Can they all have just got off the train? From Norfolk? In the 1950s?

Admittedly, the stooges were incentivised. To the tune of five whole quid, in M&S voucher form. Five. Pounds. Does that still even get you a litre of petrol? Or a Mars Bar?

Perhaps the issue here is that the passwords were so weak they were worth exchanging for a sandwich (not just any sandwich, a £5, Marks and Spencer, rocket, unicorn and gold ciabatta). You see, 45 percent of respondents to the study (commissioned by Symantec) used either their birthday, mother's maiden name or the name of their pet as a password. The great flaming idiots. No-one could guess that, could they? Certainly no-one under the age of three months. Not unless they were human.

It gets weirder. I don't know who this independent research company was, but I suspect they may employ hypnotists (or rohypnol). Either way, don't let them buy you a drink. During the survey, a number of respondents were persuaded to explain how they remember their passwords, where they store it, and which websites they use for email, shopping and social networking. To a complete stranger. On the street.

Sadly, none of this should surprise. Unless it happens to you (or you are a thief) it's difficult to take the threat of identity theft seriously. But if we've learnt anything over the past few months it's surely this: banks are not run by geniuses. It takes remarkably little personal information to open a bank account. Or even to close one.

So please don't give it up for a fiver at M&S. At least hold out for something useful like an iTunes voucher.

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