The Magnus effect is an observable phenomenon that is commonly associated with a spinning object moving through the air or another fluid. The path of the spinning object is deflected in a manner that is not present when the object is not spinning. [source]

The Magnus effect explains commonly observed deviations from the typical trajectories or paths of spinning balls in sport, notably association football, table tennis, tennis, volleyball, golf, baseball, cricket and in paintball. [source]

In this interesting example, Finley uses the Magnus effect to fly his quirky RC plane that looks more like a push reel mower than anything capable of flight.