If I could keep doing what I was doing I wouldn't care, but it's just enough to distract me and pee me off. I don't even pretend like I give a freak anymore, I just try to make no response or any gestures indicating I am listening.
After initial eye contact and greeting, I just completely ignore them and go on with the task at hand.
I don't get invited to the pub very often, but I get my work done.
I eat lunch in my office to avoid having to talk. Lunch alone, 5 minutes. Lunch with others, 30 minutes minimum. Don't they have work to get done?