Don't surf the net at work. Don't take long breaks. Don't waste time on useless things. Only show up when you are healthy and well rested. Only work with talented people who get stuff done.
6-7 hours of real work a day x 5 days a week x 48 weeks a year x 7 people can get huge amount of stuff done.
PS: The longer most people are at work each day, the lower percentage of the time they are actually getting stuff done.
Of course, the ratio of work-done to at-work is going to down as at-work goes up, even if work-done remains constant. This is why you should go home at the point where work-done equals at-work, so the ratio remains at 1, even if work-done and at-work are both less than 8. Most companies don't like people working significantly less than 40 hours a week, however.
6-7 hours of real work a day x 5 days a week x 48 weeks a year x 7 people can get huge amount of stuff done.
PS: The longer most people are at work each day, the lower percentage of the time they are actually getting stuff done.