My favorite was when I was backpacking in Europe during grad school:
"Are you carrying any crystals in your bag?"
I was tempted to say, "Well, my Waterford. I always bring that with me."
I sometimes screw with them a little bit and provide the answer to the next question. When they ask if I have a computer I say, "Yes, but it's mine and I haven't had it repaired." They have no idea how to respond to that.