After getting much-needed doses of sunshine when I'm in SoCal, spending time in Montana during the winter can be very trying. I purchased a HappyLight a couple months ago, and have tried using it, but honestly, not sure if it really helps. I start feeling the effects after just 3-4 days of no sun.... I don't know how you guys in the NW and NE do it. I wouldn't last a week. Sunshine truly makes me happy