Toybox: Physics Playground for iPhone
Update 7/15/09: Toybox has been released and is available for $1.99. Click the link below to purchase.
Toybox has been submitted to the App Store. From their website:
“Toy Box is a 2-dimensional physics playground inside your iPhone or iPod touch. Make anything you can think of, then interact with it onscreen.
Realistic 2D physics with elastic collisions
Tilt [...]