People who don't use their turn signals
People who drive 10 miles UNDER the speed limit
Those groups of people in the mall that insist on walking at a snails pace, but take up the entire aisle so you can't pass them
not putting the cap back on the toothpaste tube (my boyfriend is physically incapable of this

)
Not saying excuse me when you burp, even if it's a quiet burp.
Getting a new CD and finding out the artist didn't include the lyrics in the liner notes (I now check the side of the CD before I buy it to check the thickness of the booklet, but sometimes it's just a lot of pictures and thankyou's so it can be deceiving)
My co-worker Sean (literally every single thing about this boy annoys me **shudder at the thought**)