But theft is not the only means by which laptops go walk-about. A 2005 survey of London taxi drivers undertaken by Taxi, the magazine for the Licensed Taxi Drivers Association, and sponsored by mobile security supplier Pointsec, found that over a six-month period passengers left an astonishing 4,973 laptops behind — although 96 percent were returned to their owners after the drivers went to the effort of tracking them down.

A further 5,838 PDAs were also abandoned in this way along with an astounding 63,135 mobile phones — an average of three per cab — although in the latter instance, drivers managed to return about 80 percent.

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