[thefro526]

At the end of the season I kicked around building a trackball catapult as a possible project in school and the way I was going to do it was to have a piston retract the catapult and pull some surgical tubing tight. to get the piston to extend with the surgical tubing fast enough I was just going to leave one of the ports open which effectively makes it a spring return style piston. I figured that when you switch the direction of the piston it will almost instantly compress and shoot the ball. I'm not entirely sure it would work but if it did it would be kinda cool.