Has anyone built an Auto Focus Adapter?

With the price of used film camera bodies dropping to the floor on such places as ebay, I was wondering if anyone has taken this up - maybe a body (with the back removed) placed in a suitable case with the GG up against the film rails - a simple button press puts you in focus - then use mirror up or B setting for shooting.

I have seen many people use a camera for a 35mm adapter but instead of removing the back they have just focused through the viewfinder.

My first 35mm adapter was based Canon EOS AF camera, long before I came across these boards here. Even continious AF worked quite well.
But then came all the grain and bokeh issues and better camcorders couldn`t focus on view finder... Guerilla style (http://www.cinedof.com/img/IMG_9551-01.jpg)

Cheers,
T

concept - wise that looks good

I was maybe thinking about the little Canon HDV HV10 mounted upside down at the back of a 35mm body (so now its a top loader!!!) with an APS sized GG vibrating in the space between the film rails.... or a spinning/rotating GG powered from a motor tucked inside the film cassette storage space