Are you Andy?
I say no, and he looks a little puzzled, but then continues:
Oh. We can't make the projector work for our meeting, and when I asked for help and the desk upstairs, they said come down here and ask for someone. I forget what name they said, but they said look for the redhead, so I just figured your name must be Andy.
And yes, he was serious, but he did apologize when I said my name is Brian.