Anyone with a London cabbie in the family will have heard stories about who or what they've had in their taxi at some time or other.
Chances are they've found a few mobile handsets nestled down on that back seat (along with all those forgotten cameras, Ant and Dec and "that bloke from Eastenders, whatsisname?").
In fact, the last six months alone have seen 55,843 mobile phones left in the back of London's black cabs, according to research from Credant Technologies.
And that's not all - there were another six thousand other handheld gadgets and gizmos left there too, including laptops, iPods and memory cards.
But never fear, London's cabbies are an honest lot – 80 per cent say they reunited the lost gadgets with their owners. In New York it's nearer 66 per cent.
Of course, some people don't want their stuff back - one London cabbie was even given someone's drunken wife as a tip.