Hey guys I decided to play around with collision/physics using particle systems and some hinge joints and created this: Energy Swipe to move the orbs Pinch/Spread to zoom http://appshopper.com/entertainment/energy Its a FREE app that is like Newtons Cradle but only with 3 "orbs of energy". Red, Green, and Blue of course. It also has a snow effect that bounces of the orbs. You really have to download it to see it in realtime or check the link above for screenshots. App Store Link I am taking suggestions to improve upon the app. Any cool effects you want to see let me know. It will always be free app. It does have 10 pixel width ads on the side.