If I were super filthy stinkin' rich, I would fund a project to make digital back for old 35mm film cameras. I know, it has been tried-and-failed before, I know. But heck! The sensor tech gets ever better and thus it might get ever easier to actually make. Random example: the sensor technology is such that one could even just be videotaping everything coming through, and then pick out capture frames later. Or, have the digital back do that for us, and snap out the non-dark images. Works fine for non low-light long-exposure situations. Or, set the back's ASA to 1000 and then notice when there's non-blackness and get a raw shot, because the film camera is probably set at like 200.