Litter built up on trains because cleaning crews could not get on often enough. More staff was the expensive answer, instead we made the bins impossible to miss, and more fun to use. We knew an engaging product could lift deposits by 41% in a single day, simply by making the act rewarding. Salience plus a little delight beats a fine. People already knew where the rubbish should go; they needed a reason to bother mid-journey. Noticeable, slightly exciting bins did the psychology and the train got cleaner without a new roster.