Well, some guys in the last issue of Brittish Medical Journal claims so! Please find out if they are telling us the truth.

/Mythbuster fan from Sweden

i'd seriously doubt it. Lightning (as i know) strikes the tallest objects in an area. If you're on a field with no trees and you're the tallest thing on the field than lighting will probably strike you. And as i know it tends to strike metal objects, but nothing to do with mobile phones. But i'm no expert so i could be wrong...

It depends if you're looking at the effect of a mobile phone on someone's behaviour as to if this myth is true or not. If they were in a building that had poor signal, they may go onto the roof. In another case, someone is in the middle no-where, but they have a faint signal if they put their hand right up in the air, to send a text. In both cases the mobile directly put them into more danger, simply by trying to get a signal.