One of the best treatments for S.A.D. (Seasonal Affective Disorder, for those not in the know) is to hit up the tanning booth for a few minutes a week. Even just a 5 minute session twice a week will improve your outlook.

If you don't want to go to the fake 'n' bake salon, then check out getting an Ott Lite bulb for your desk lamp. Full spectrum plant bulbs will alleviate some of the "short days, too little sunlight, too much 60-cycle hum lamps" blahs that many people are prone to over the winter months.