1) "smackers" whether that be chewing gum, or eating with their mouth open, or even those odd people who make random smacking noises with their mouth.
2) People who blow their nose loudly, or clear the drainage in their throat in public places, especially in a restaurant at the table behind me
3) The phrase "right on". Really what is that supposed to mean? The way it is said most of the time is also in this deadpan, no emotion way that let's you know in no uncertain terms that the person is just being patronizing.