Back then in my school time Curveball was one of the first flashgames I played. Secretly it was played while our teacher was just not looking in the computers room. The game itself sets place in some kind of 3d-room where we have to beat the enemy like in the classic Pong. We have to score the ball into the goal of the enemy. Therefore we use the "mouse" or the "finger". A little bit harder to defend because the ball will move strongly before it reaches our goal. It needs practice and skill.