Deer are stupid. Whether they hear you coming or not, they still might run right in front of your car. It's happened to me several times in just the last year. A deer is on the side of the road. As I get close it starts to run. Half the time, they choose to run across the road instead of running away from the road on the side they're already on.

I haven't hit one yet, but that's entirely due to my own corrective action. The deer deserves no credit for being a good survivor.

Take an old harmonica instead and glue it to the front of your car.