Wendy Boswell of Lifehacker has done it ! The Boswell family has apparently been planning this for a while. They both had side business which were making money. They had decided on a threshold, when reached, they would quit their daily jobs and get full time on their side businesses.
Wendy has documented the stuff that they have been thinking about, and what anyone should think about, when making a change (or thinking about a change).
Check the post here.