Here's a pretty funny story - a Bulgarian customs official stole a mobile phone with GPS and was caught after its rightful owner pinpointed the device in the culprit's pocket!

US ambassador John Beyrle was en route from Varna to Hungary when he submitted his hand luggage for the usual x-ray inspection. His phone subsequently did a disappearing act, and an airport staff search for the missing mobile proved fruitless.

Beyrle, however, powered up his laptop, activated the phone's GPS which revealed its location aboard the light-fingered ne'er-do-well. The master criminal and an accomplice were cuffed and now face the sack plus malpractice and theft raps.
All I have to say is... nice one!