I posted up some x-rays we did a while ago for Ortho-On-Call. Well this is something that goes kind of in the same vein. Artist Evan Roth designed and made these metal plates that people can slide in to their carry-on luggage to give the x-ray readers a little message. Because the plates are metal, they will show up basically as solid white on the x-ray, and obviously the cut out parts won’t. Pure genius. Link courtesy of BoingBoing.