The sad thing is you could never get away with something like this now-a-days. Not that it would be successful anyways, but hey, I like experimental options.
Summerhill is still operating: http://www.summerhillschool.co.uk/ As is Sands: http://www.sands-school.co.uk/ And a number of others. Many schools (usually pre-schools admittedly) based on the works of Montessuri and Steiner are all running worldwide. There are also many schools in the UK which have blended a little of the 'free school' methodology into their curriculae. My nephews go to one. They're smart little buggers and expect reason instead of authority when we're discussing and deciding plans which is enormously frustrating and deeply reassuring.
I guess I should have mentioned, you wouldn't be able to do this in the US. I know absolutely nothing about UK law. Granted I'm still probably wrong. But that's cool, thanks for the info :)