After normal questions came "are there children of whom you're their father, but upon whose birth certificate you are not listed as the father?" Uh, wha? Turns out this is pretty common in some countries, and the US govt wants to make sure it knows what it's getting in for, and that you don't later claim all of Grodblockistan as your children and thus sponsor them for visas.
Then he asked "did you enter the US for the purpose of practising polygamy?" I turned to Jenine and said "uh, honey, could you leave the room?"
There was a pause while the interviewer opened and closed his mouth and tried to work out what to say. Then Jenine and I laughed and I said "of course not". The interviewer's composure was not the same after that.