GE Motion Switch

If you do go with that switch, head over to here for the official unoffical DTH for that device:

To answer your question, you can do this with any motion detector…the switch makes it easier to turn on the light as you would set it to “occupied” and when motion is detected, the light would come on. However, the other things you want (alert and other lights coming on) would have to be done with something like WebCore.

Good luck and don’t hesitate to ask questions!