I've had SAD since I was in college. Before I knew what it was I referred to it as "the slide down into the dark." I had a really hard time with college winter break, which was 6 weeks long in December and January.

I've found that what helps best is getting outside as much as possible. I've also found the exercise helps, and outdoor exercise is the best of all. Having a project that you can work on when indoors helps too.