I think that separation is the wrong goal.
The goal should be that work becomes life.
But apart from that:
A speech from Jeff Hawkins who achieved great things in multiple field (which not many people do these days) where he talks about his approach to to balance his life:
Stanford's Entrepreneurship Corner: Jeff Hawkins, Handspring - Work/Life Balance
But what does he know? He only created a company that lead the field of handheld computers and wrote a breakthrough book about neuroscience on the side.