People that don't give me the courtesy of a 3' buffer, as I ride my bike (with traffic), to and from work. If I rode at 18-25 miles per hour on the sidewalk, someone would die.
It's called a "road bike" for a reason!
People that honk at me as I'm riding my bike along with traffic.
Well, one of MY biggest pet peeves is bicycle riders who don't follow traffic rules. In my state they are to follow the rules of the road the same as motor vehicles. I see them ride between cars between lanes, never stop at lights or stop signs, weave in and out of traffic, turn left in front of a line of cars on a red light. As far as I'm concerned they are a hazard.
Head down, Feet pedaling, means don't bother me, just ease over and pass by.
The law, at least here in Florida, states that I am allowed to ride along with traffic, as I am a vehicle.
http://tampabaycycle.blogspot.com/2007/08/3-foot-law.html
http://www.floridabicycle.org/rules/bikelaw.html
Sorry, but one of my pet peeves is people that don't understand/obey bicycle laws, as I'm a bike commuter.
All the rest of my pet peeves have pretty much been covered in this thread. Oh wait, here's a couple.
People that let their dogs go poo and pee in their yards, and then let the kids go out and play in the same yard.
People that are on welfare or live in low income housing, yet drive fancy cars, with fancy rims and all of the stereo equipment, ta boot.
People that have crappy cars, with nice rims and tires.
People that let their children walk barefoot, wherever they go, IE the supermarket, public restrooms, etc...