HypnoPhone is a ‘game’ I made last spring when I was first learning how to get stuff on the iPhone. It was pretty basic, but has some measure of popularity in the App Store. A few weeks ago I completely rewrote it from the group up, and it was just approved!
This new version is faster, smoother, and most importantly, now has a speed slider to adjust the spinning speed of objects. Just touch the screen near the home button to see the slider, and touch the screen near the ear piece to go back to the main menu.
You can check out some screenshots of it in action by visiting the games website.