If you get gloomy in the fall/winter with the shorter days (and if you live in these parts with all the rain) don't despair, just give one of these little suckers a whirl. It's light therapy and you may not need it at all, but I sure do.
I lose that spring in my step after a couple of months without much sun. Everyone's different though. For instance my partner has no problems at all with the lack of sun. For me my sad lamp is a staple, and as soon as I wake up it's me+coffee+sad lamp every single day (while I'm in Vancouver anyways). I begin around now and go straight through the winter and early spring. They are a little pricey though, generally running $200-$250.00 plus. Personally I truly can't imagine not having one. It has changed my life out here the past few years.
As your light exposure decreases in the fall and winter, the general consensus of the experts is that these changes in light exposure affect the body’s natural rhythm and chemistry. There is tons of research and info on the web so I'll leave that to you. For as long as I live in a rainforest I will be sitting in front of my light box every morning in the darker months. (although if you suffer from depression, are pregnant, taking light sensitive medications, suffer from any health issues that you think may prove a problem I would talk it over with your health care provider before making the investment). For me it's money well spent.
The one thing to make sure of when purchasing one is the strength needs to be what's called 10,000 lux (or it's pretty much useless). Light therapy can help with more then the winter blues as it helps to set our circadian rhythm. Its good for seasonal depression but it's also good for shift workers, jet lag and a host of other situations. Again, it may not do a thing for you, but I swear by it. Thought I'd share. Namaste.