LIGHT BOX INFORMATION
For folks that suffer from S.A.D. (Seasonal Affective Disorder), Zorba recommends using a light box. He explains that SAD has little to do with temperature, but rather is a result of the limited daylight from the winter months. The lack of light decreases melatonin production.
To combat this Zorba suggests spending 20 - 30 minutes a day in the proximity of a light box. Here is a link on how to make one at home. Another one here.
He also suggests regular exercise and (if need be) talking to your doctor about anti-depressant drugs.