On a trip to the middle East in 2005, I carried one of those squeeze filters because the local water was funky. The screener in Switzerland saw it on the x-ray and went nuts, then he looked at it and saw what it was. He called me back behind the checkpoint to show me what it looked like on film. We had a good laugh. I told him that I wouldn't have let that one past either. It looked like a stick of dynamite suspended in liquid. This all pre-dated the liquids limitations on airplanes.