I've been playing with this idea. Planning on making an attachment for my 3D printer, but haven't gotten around to it yet - for scanning medium format negatives
I would love for the hacker crowd to start looking into repurposing old scanner technology.
I am waiting EAGERLY for the first open source scanner made for negatives. It's so sorely missed, and so far i'm on my third flatbed and not happy at all. It's silly when the line-scanner is the same for all of them more or less.
Someone should really do a reverse engineering on some of it.