Volleyball!
While the packaging promises "an electronic simulation so real you can even spike a shot", this is in fact a volleyball game which has a very loose interpretation of the standard rules. In fact, it can be described as a cross between volleyball and Pong: Each six-man team is separated by a large line, which the casual observer would interpret as the net. The line is open at the top, and this is the only place where the ball can pass through into the other court. While the ball is in your court, it can be passed as many times you want, and bounced against the "net" and the back of the court. As long as the ball doesn't touch the bottom of the screen, it is safe. The joystick moves the entire team in strict formation, and the ball passes through the players if they are held still, or bounced in the direction they are moving. A status display at the bottom of the screen writes out in clear text whether there is a serve change, a spike, scoring or otherwise.