Derived from Chapter 6 of Big Nerd Ranch's excellent iOS book; I got bored and skipped ahead and made this.
It makes trippy colours when you tilt your phone (or if you're using the iOS Simulator, it will make trippy colours when you swipe across the screen).
See JGHypnosisView for more details. Rad.
If someone could explain NSOperationQueue to me that would be great - totally fudged at the moment.