Summer Fridays are a thing of the past ... Remember the good old days when, during the summer, you'd work nine-hour days Monday through Thursday, and then leave at lunchtime on Friday? If you're wondering what happened, you're probably not alone. Just 11% of North American workers say they are allowed to do summer Fridays. What gives? Apparently, many companies believe that allowing you to work from home once or twice a week offers the same kind of flexibility. But HR expert Caitlin Duffy tells NBC News that it's not equivalent. She says, "Organizations may see them as interchangeable, but there’s something different about being completely off and disconnected than there is working remotely."