In any sufficiently large organization there will be
lost files,
ones that are physically present but "lost" due to the owner
keeping important contextual information with him and either
leaving or dying. These lost files could be either paper or
digital; doesn't matter much.
sufficiently large = 15+ people
sufficiently old = 10+ years
yes, this is true for the architecture firm I work for.
Some earliest work didn't get archived. A *very* few
archive disks (128MB and 230MB M-O) have developed
problems that cause the loss of one or two files.
But given the way they organize their CAD here, the
floor plan or detail info they need is often contained
in another drawing.
We did some early visualization work on the Mac using
Gimeor's Architreon, which is a dead product that never
made it to another platform. However, I have been opening
the animations and taking snapshots, frame-by-frame, so
I can bring those animations over to the PC and show them
there.
It's a lot of work, admittedly...
-dq