Interesting thread, I have always used an old pop bottle, but I have an uncle from MN, who comes here to MO. to deer hunt everyyear. As soon as he gets 30 yards from his stand in the morning befor sun up, he drops his pants and plants a duece. He kills a big buck every year that stops by to take a whif. He swears by it! I still can't muster up the courage to try it.