This tops my list for sure; I call it a "moving roadblock". When I see this, I make a point to ride the offender's *** as closely as I can.
Interestingly, another peeve is when people ride my ***...but this is only because it's unjustified because I'm always right. I have the same philosophy
Number 2 is when people who don't use cruise control pass you and then slow way the **** down, requiring you to pass them...especially when it happens multiple times. I once had a guy pass me 7 times between Rockville and Germantown in MD, which are only about 10 miles apart. Especially when you actually start recognizing the person in the car rather than just the car itself...
Number 3 is when you absolutely need to get over into another lane and nobody will let you do it. People are awful about this on the East Coast. Agreed... On the east coast you have to force the issue and take the spot. Usually they cave if you get your front wheel in there
Number 4 is when traffic converges or a lane is dropped and some ******* decides to drive on the shoulder and cut ahead of everyone. Okay, I'm a left lane zipper merger, but totally agree about this. This is an east coast thing as far as I can tell. I've actually seen cops waiting at the end to pull these people over, they usually have 1 or 2 lined up getting tickets.
Number 5 is when you're at an intersection waiting to turn, and the person behind you starts honking...as if they have some knowledge about the cross-traffic that you don't. If I'm not turning, it's probably because there's still traffic coming, jerk. Amazingly, this only happens to me in MN somehow.
Just thinking about all of this gets my blood boiling.