Although I have seen it accross the board. A person who is normaly great to play with but get him into a tournament of some sort and BAM the devil takes over.
Then I have seen myself get bummed out when I have the bad dice days...but a good player will play where the dice dosn't control the outcome...even though some times if you roll a "1" SIX TIMES IN A ROW FOR MORAL OR SOMETHING IT MIGHT BE TIME TO JUST BE A SPECTATOR THAT NIGHT. I can't say I ever picked up anything and threw it. Especially my miniatures. To much time painting them.
Yet I know my gaming buddies call me Meat Hooks (picking up miniatures made me think of it) cause when I first got into the gaming group 9 years ago a friend of mine had painted up some 40K figure (he dosn't play it but loves to paint the figures) and had this sword on it that was painted up as some sort of energy sword. At any rate I was looking at it and what do you know I was being so gineger with it I droped it.
Right on the tip of the sword on a cement floor. 
Nothing happend except had to gingerly bend the sword back but no chipping.But the name has stuck since then!
I would have to agree with the person about the FOW gamers though they all have acted like adults thus far.
Had a person storm out the door because he was 15 minutes late for a scheduled game and we started it (huge 10 player game that we play once a month follwoing Formula De schedule) on time...actually scratch that we started it 10 minutes late so he was 25 minutes late. Even went as far to slam the door to the club. Proably just a bad day prompted it though.
Sean