I take a Milkweed pod when they are just about splitting in the seam and place it in my hunting coat pocket. When I bow hunt for deer from a tree stand, I take out a milkweed seed floater, and release it to judge the air currents, and see where my scent is going. Free, and easy. Better than a squirt bottle of talcum powder because not only do you see the direction of the wind, you see where the wind is swirling.