Good news for all those with future iPad 2s that have a broken sleep button: With a magnet you can do the same thanks to the functionality that Apple has included to support the Smart Covers.
In the video it is seen very clearly, if we put a magnet where the Smart Cover go, we will obviously get the screen to turn off and the iPad to go to sleep automatically, and if we lift it up, it also comes out of sleep.
As simple as physics itself ...