The U.S. military has been studying the suicide rates of it's members and one of the aspects being looked at is the occupation held by people who suicide. A basic summary of the results of studying possible relationships between occupation and suicide in the military can be found here. According to the study the most suicide-prone job in the military is:
French horn player
Yeah. I suppose if my job was to blow on a horn I'd eventually want to kill myself, too. At least whistle blowers can have some sense of purpose in life from what they do.