An alarm clock that shows you that other people are awake
Know the feeling when you wake up, and it is pitch black outside, and you think it's a mistake? The clock says 7am, but honestly, it could be wrong, right?
I hacked a Chumby to show me a live webcam feed from a camera pointing out the window to the street. That would be proof that it is indeed morning, and other people are responsible adults with their jackets on already.
At night, it shows a feed from the airport with the planes landing and taxiing to their gates. Not seeing any planes means you're up too late.