I am working on a tool to help growth stage startups manage their growth better. We do that by providing a simple app for tracking company wide expenditure and then providing insights highlighting opportunities for better manager of finances.
I think the more relevant question might be, how do people handle their three day weekends?
I've tried out all levels of weekly work hours. Too little work can be very difficult to deal with. After years of trying out 1,2,3,4,5,6 and 7 day weeks, I've settled back to five.
Remember, not all of your friends will be available to hang out on your extra day. Have you got a specific use for the time?
By all means, give it a whirl. My 2c would just be to find something to fill that extra time with.
http://www.rubberstamp.io