Great suggestion! My husband and I individually impose our own "no screens days". Him on the weekends because he is a software developer. I had to do one last week because I had gotten involved in so many social network conversations that I seemed to be continually checking for responses! I ended up getting a lot of things done that day and my kids were happy and cooperative. The threads and messages and emails were there waiting for me the next day
My children are still young and don't use screens everyday. As far as I can tell they do fine without those things and are happy when mom and dad are not preoccupied by electronics.