Sure, this hack has been done before. There are many people who have their own designs, own ways accomplishing the same objective: 35mm depth of field on a digitial video camera. But the boys and I have never done anything like this. We set out to make the most hacky device that would still produce video that could be considered watchable, and we knocked her out of the park.
Just what am I talking about? Check out the project page for all the details and sample video.