People honking at me when I'm driving (actually, just honking at all). Well, unless it's justified, like if I start changing lanes without seeing someone in my blind spot.
But a couple days ago I was waiting to pull out of a parking lot after picking up some food, feeling a bit relaxed and looking for a decent break in the traffic. This huge truck pulls up behind me and after twenty seconds or so starts lightly tapping his horn for a bit. Maybe a dozen little taps. I look back and it's this middle aged man with sunglasses and one of those ex-high school quarterback haircuts. The traffic picks up again and I obviously hadn't taken the opportunity to pull out yet. He starts honking some more, and when the traffic dies down, I just sit there sipping on my Coke, trying to get him to see me through the back window. I wait there for about thirty seconds longer as he revs his engine behind me, and I unbuckle my seat belt and pretend to reach into the back seat for something. He pulls out beside me and speeds out of the lot in front of someone, almost getting hit.
I laughed, took one more sip of Coke, and immediately pulled out.
Douche.