One more thought on the "positive" versus "negative" thing - I think it is INTENSITY of feeling that generates creativity - and it may be that negative feelings are more often classified as intense than positive ones. That's why people associate negative experiences with being artistic inspiration moreso than positive experiences. But, as several people have already illustrated, strong positive emotions can be very artistically inspiring as well.
And Kirk, as far as the ADD thing goes: are you STILL talking about that?
