Cure For Depression?

I wonder what the psychological community would think of this treatment method (or if something similar has already been tried) for depression: Watching videos of babies laughing. The one below is my favorite, but the related videos show that there are lots of babies out there with great laughs. I have marked some of them as "favorites" on my YouTube account. In the event that I have a bad day, I just watch the videos and laugh along. I'm not exactly your typical example of a major depressive, but it works for me when I'm feeling a little sad. I wonder if it would work for someone feeling a lot sad...