Go to any level that has a Toad (or just stay in Delfino Plaza and find one) and stand right beside him. Jump once and watch as you start bouncing in thin air. It will make the same sounds and effects as if you were really jumping on him, but if you change the angle of your camera, you will clearly see that you are only beside him. This may only work with Toads.
Submitted by: Mitchell VanRassel