Pong Multiball Extreme is a very hard online game by Agent Veggiepuff. It plays like regular pong, only you start out with 25 balls, and each time you hit the copy ball (the ball with the green core), a new ball is made. It was made for Pookies to play, so they would get so angry they break the computer so the mumu/duh duh throws their Pookie out and never adopts a Pookie again. The balls don't separate until they hit the paddle.
A link is here, if you are calm enough to play. Trust me, it is more anger inducing than Flappy Bird.