My peeve — on single-lane roads with passing lanes, the people who drive really slow on curves and non-passing sections, and then accelerate to 10mph over the limit where the road is long and straight enough to pass.
I know that it is likely they are simply driving as fast as they feel safe, and aren’t purposely trying to prevent people from passing. (You know that type, they wait until you are halfway past them and then they speed up to make it hard for you to get by). But it’s still anooying.
Whenever I see someone passing, I slow down to make it easier for them.
Also annoying — people who pass you in a passing lane, and then drive slower than you were driving.
Ooh - also - the folks (usually seniors), who see you driving along, yet quickly pull out in front of you from a gas station or parking lot.....then drive much slower than you.