* Women who take forever using a public toilet, because they feel the need to apply makeup while they're there... and meanwhile you're standing outside ready to burst....
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The last time this happened I was on the road and suffering the effects of several morning coffees. When the woman finally emerged under numerous layers of warpaint and reeking of cheap scent, I told her that in her case it was a waste of time

Yes... I know.. not very nice at all.. but by that point I was in real pain.
*People who leave cell phones on in movie theatres and restaurants... and then proceed to talk loudly enough for everyone to hear.
*When people talk at length on a cellphone when they are supposed to be spending time with you
*People who talk on cellphones while driving
*People who smoke in public places, either inside or outside.. it matters not to me. Breathing in second hand smoke is disgusting, especially when you have asthma.
*Hypocrisy. It really bothers me when somebody is all too quick to point fingers yet never sees their own reflection in a mirror.
*Big Egos. IMO, there is no need or justification for a big ego, ever. One's accomplishments should speak for themselves.