Tight security
I regularly travel through Belfast city and recently the security chap wiped my laptop with the the little paper disk that they then feed into the scanner to detect any explosive content. I made him aware that I regularly indulge in pistol shooting and that the dark stain on my forefinger was actually gunpowder residue from the day before (yes I had tried to wash it) and he said that the scanner would pick it up, nary a bleep from it. That really builds confidence.