Saw this over at Gizmodo. Granted, Gizmodo wasn’t the original article, but if you like prime sources and can read Finnish then feel free to click through the link they provide.
In the US hitting deer with your car in the middle of the night is a real problem, not just for the deer and your car, but for your health. In Finland they have the same problem but with longer nights and bigger animals: reindeer. Rather than continue to run over Santa’s four-legged helpers, they use reflectors to draw the attention of drivers. But reflectors worn by reindeer are less than perfect because the light has to catch the reflectors at the right angle. But spraying their antlers with a reflective substance takes care of the angle problem (360 degrees of antler!) and makes the animals incredibly noticeable. A simple, elegant solution to an every day problem (if you happen to be a Fin who spends every day driving in the dark in reindeer territory).