I started zapping several weeks ago, however last weekend when I had to travel on a plane, I decided to leave my zapper at home. I was just to scared to try and take it through an airport. And if I couldn't get it through an airport in Australia, there is no way I would even try in the US. Just had too many bad experiences with travel between our two countries (not to mention domestic US travel).
Americans love to talk about "Freedom", but as an outsider looking in, it is frightening to me just how little freedom you actually have left.