Full arm roll (backhand release) - Roll the hat from hand to hand along outstretched arms
Hold the hat with the crown back in an inside grip in your outstretched right hand. Flick the hat so that it spins up out of the back of your hand onto the arm and rolls across the back of the neck (make sure the head is ducked forward out of the way) and down the other arm.
As the hat reaches the other wrist bend the hand up and catch it in a inside grip.
Make sure the arms are sloped so that the hat is always rolling "downhill", and practice, practice, practice - this is a difficult trick.
From the TricksWithHats archive