Out of hand Your hand is fantastic for inducing Rotation. The reason for this is because of your hand's shape and "stickiness". Your hand is can shape it's self in two key shapes a wedge and a hook. Wedge's are great for rolling object. The angle of a wedge cause the force of gravity on the object to be partially diverted and will cause the object to roll down the wedge. shaping your hand in to a hook lets you induce high angular velocity (speed of rotation). In ideal situation objects won't slip but if you over come friction nothing stick. Good thing for your hands they have a high friction coefficient meaning your hands are "sticky". This lets you grip objects and induce forces  on them.