It was made famous by the film 'The Mighty Ducks', where it was the ace-in-the-hole of streetsmart player Russ Tyler (Kenan Thompson). As Russ, the Los Angeles native, explains, "It's hard to be accurate, but it drives goalies crazy."
In the movie, the knuckle puck somehow sails through the air along a physically impossible sine-curve, causing the opposing team to stare in confusion as the puck whizzes by them and into the net. In reality, hitting the puck from the side as Russ does results in a disappointing shot that bounces chaotically and stops after a few feet.
Children and inexperienced players often attempt this technique, but the shots are slow and inaccurate even for the best of players