40 in 4 or 40 in 5?

This past week I rediscovered a thought I have had almost every 3-day weekend I have ever experienced. What do we – as the American workforce – accomplish on day 5 of our 40-hour workweek that we could not finish up on day 4?What could be gained from a 4-day work week and what could be lost? There seems to be so many angles: family time, quality of life, length of workdays, stress, revenue, etc. GO!PS – For a good read on a 4-day experiment: http://www.time.com/time/magazine/article/0,9171,1919162,00.html?iid=digg_share