I have had many events that have raised my blood pressure in WoW, but only one where I can actually say I was so scared that I think my heart missed a beat or two.
It was in EPL and I was getting the doll parts for Pamela. It was about 2 AM, and I was tired, but I was just doing "one more quest" after doing about a dozen "one more quests"..... and I went into the house, and the invisible mobs popped, and shouted....
I damn near had a mini stroke!