Well, in terms of distraction, I'm not meaning that you throw it out so the enemy troops walk over that way and check out what the noise was in the way Thief or NoLF did. I'm meaning when you run out of ammo and you got nothing else to use, you throw your helmet at an enemy soldier in front of you if there is one infront of you and he has to get out of the way, those few precious seconds you could use to draw your knife and continue with your attack.... I dunno if this could be implemented, it seems like a cool idea, and I'd sure as hell like to see it, but whether or not it could be done is a different question.
Still it's worth asking.