Doug says: "Every year on 4/20, students and residents gather on Farrand Field at CU Boulder to defy the authorities and smoke marijuana publicly. This year, the University of Boulder Police Department fought back by taking pictures of as many participants as possible. They have a website with photos up, offering an $50 reward to anyone who positively identifies someone who was photographed. Nothing about what the authorities plan to do with the information is posted. Scary." Link