Sunlight Alarm Clock

I always feel better when I wake up by the sun rising slowly on my face. However, if I were to wake up to the sun every morning, I'd have to wake up later and later, then earlier and earlier based on the season which is not very useful in a world where time precision is so important.

This alarm clock would be a set of mirrors (or perhaps some sort of refracting glasses) which would be calibrated to your room so it knows your windows and where your bed is. You'd also give it your latitude, longitude, and altitude (or it could figure these out with fancy instruments).

Then, based on when you wanted to get up, it would calculate the angles to tilt the mirrors so that the sunlight would start rising on you say 20 minutes before, to gently wake you up. It would also feature the more standard sound alarm clock as a failsafe if you were particularly tired or it were a particularly cloudy day.