A study about productivity (or: "how I just spent 45 minutes making screenshots of movies on Youtube and deciding what photo to use"). Also, 7 other things worth your time.
Researchers in the United Kingdom designed a human lab experiment in which they used "happiness shocks" (which sounds potentially R-rated, but isn't) to improve workers' moods, and measure how happiness affects their productivity.
The results will make you smile. They recruited 700 university students and assigned them tasks as part of an experiment.