Germs spread quickly. Antiseptica, a German hand sanitizer, can help. But how do you show just how quickly bacteria and viruses transfer from hand-to-hand? Grabarz & Partner used the Hamburg Marathon's 80,000 spectators to make its point. It gave six marathon runners stamps and ink bands that they ran with. As runners passed spectactors, who would reach out to give them a high-five, they would stamp "ads" for Antiseptica onto their hands. Anyone coming in contact with those runners would see, in big letters, "That's exactly how nasty germs spread," stamped onto their own palms. Promo teams also fanned out and handed out the disinfectant on the spot -- letting the spectators wipe away germs, and also the stamp, quickly.