Here’s a creative use of a notebook and its internal motion sensor.

The application i wrote reads out the Powerbook´s sudden motion sensor´s position data and then uses it, to move the marionette accordingly. If you tilt the notebook to the left, the marionette on the screen reacts to gravity and also swings left (and vice versa). To see the marionette in action, you can watch the video below.
The next step would be to equip two or more laptops with the handles and stage a play at your local kindergarten.