Magic Window was one of the first apps on the App Store when the store launched. It is a simple idea, but wonderfully executed and now available for the Mac as well as iOS. Magic Window is time-lapse photography for iOS it serves as a relaxing picture window and on the Mac it can play on your desktop. Plus, by adding a projector (in the video below it is connected to an iPhone) you could have an enormous wall of a sunset slowly changing over time.
Theres really a bit more to Magic Window than mere novelty, including weather (supporting micro-climates as you find here in San Francisco), sleep timers and an efficient use of your processor. Check out the demo below by Josh from Jetson Creative, the smart folks behind this wonderful app.