Wintergreen oil has a minty, cooling, tingling effect when applied to the skin, which provides a nice relief for sore muscles. Like capsaicin (the component in peppers which brings the heat), a few drops goes a long way!
My yoga teacher introduced me to Deep Blue Rub ($39), which, in addition to wintergreen, has menthol and camphor to boost the "icy" heat. You only need a small pearl-size bead to feel the effect. If you use either, apply after a workout (not before) and wash your hands thoroughly with soap as soon as you finish applying or else your hands will start to burn (and you may accidentally touch your eye). I usually apply the oil with the base of the glass container or a plastic cap to avoid touching it all together. I apply this oil to my neck, shoulders, back, and hamstrings, which seem to need a little numbing after a rigorous workout.