In the reverse situation, I had a passing aquaintance with a pagan, one who was definitly on the 'iffy' side of the religion. He was the 'anti-everything else' type, and described when he was having a bad day and his car was being towed. He was in the front cab, and the truck was driving in slick rain and thunderstorms. He saw that the car in front of the truck had a Fish sticker, and he was feeling particularly bigoted (my words, not his) so he cast an 'instant karma' spell. Sure enough, the car in front crashed, but what he hadn't intended was that it hit the truck that he was in. The car and the people inside were almost totally uninjured, as well as the truck driver, but he managed to get a broken ankle and his car (the one that was being towed) was further damaged.