Two pet peeves.
- "4am in the morning". As opposed to what, 4am in the afternoon? I'm quite happy with "PIN number", "ATM Machine" grates slightly, but for some reason, "AM in the morning" is the equivalent of nails on a blackboard. Amy committed this one regularly, so it's probably good that things never worked out for us - she'd have slowly sent me mad, too.
- TV advertisements that have modem noises in them. It's turned into the signifier of "Internet" in your advert to have the sound of a modem handshake in the background. My modem is right next to the TV, so I keep thinking the damn thing is redialling when it isn't.