I created a basketball balancing game for Esurance.com. This was originally built as an expanding rich media banner that appeared on nba.com.
The game is fairly simple–you move the hand around to balance the ball, and you click the mouse to increase the ball spinning. The faster the ball is spinning, the easier it is to balance the ball.
The game is built in AS3, using a few frameworks, most notably Box2D for the ball physics.