Facebook has a Happiness Index drawn from posts - NYTimes.com

HEY, America, to quote the relentlessly upbeat temp in the movie “Office Space,” it sounds like somebody has a case of the Mondays.

There is a 9.7 percent increase in happiness on Fridays compared with the worst day of the week, Monday. That is among the discoveries made by Facebook researchers with access to two years of anonymous “status updates” from 100 million users in the United States...