Few months ago at SEA I watched a cat go through the scanner.

I thought the woman in front of me was just laying a largish carry-on on the belt. I didn't realize what was happening until Mr. Kitty poked his head up to the air vent in the bag just before he got irradiated. I made a grab for him but it was too late.

No real harm done. Slightly higher risk of cancer to Mr. Kitty and an embarrassing lecture from TSA to the owner. I got to see the X-ray on the monitor which was kinda cool.

Other than that I can't say I've ever seen a pet owner being less-than-intelligent on a flight.

OPos.