They all make my teeth itch, no doubt you have your own phrases that make you somewhat uncomfortable...do share. There is a slim chance that some may listen :-/
As others have said about "can I get ...?", it drives me nuts. I work in an amusement arcade and I almost want to slap people when they say "Can I get a pound of 2ps?". No, I will get them for you. You can't come in here.