I have mentioned my experience with an amazing Dawn simulator to many here, and I found a link to it: http://www.lighttherapyproducts.com/sunrizr.aspx
I just got a lamp from Target: http://www.target.com/p/Room-Essentials-Desk-Lamp-White/-/A-12227117
Then put a full spectrum light bulb in it, pointed against the ceiling:
http://en.wikipedia.org/wiki/Full-spectrum_light
I use this instead of an alarm clock. I started using this in 2002 and have never considered going back to a normal alarm ever again.
I set dawn to be a 6:00am and the light starts turning on a 5:15 (45 minute dawn cycle)