Simplicity is the name of the game. 20 levels to test your skills of aim and timing. Get each colored ball into the same color bucket by striking them with invisible vectors of force. The fewer strokes it takes to complete a level, the higher your score.
The mouse controls everything. When you bring the pointer near a ball, a little arrow appears. Hold the mouse button to build up power, and release to fire the ball in the direction of the arrow.