Many people have been upset at Facebook for their recent psychology experiment where they altered the normal content that would be displayed in a user's NewsFeed in order to see how that would change their moods. Whether you agree with Facebook's right to conduct experiments in this manner or not, it is very easy to understand why many people would be upset at this. Well, in a fantastic bit of viral marketing, a company called Just introduced 99 Days of Freedom, it's own psychology experiment that urged users to see how quitting Facebook for 99 days would affect their own moods.
Movements and campaigns to quit Facebook en-masse come out every once in a while when bad news about Facebook comes out, so this isn't anything really new, and probably no more than a few thousand people will probably end up seeing this experiment through to the bitter end. But as somebody who is interested in psychology, it would be interesting to see a study where people did measure their mood and the affects that a reduction in online social interaction had on them.