I previously built this camera,
http://www.filmwasters.com/forum/index.php?topic=5880.0, but it was not ideal as you needed a changing bag to remove the film and focus each shot.
So, with a polaroid 600se adapter, a rollfilm and second packfilm back (thank you skorj!), some lenses, some DVD cases, some old bellows from a polaroid 800, some felt and some woodwork I remade it (version 3).
Now, you can focus on the ground glass, swop backs and shoot away with no changing bag. You can use rollfilm or pack film. you can swop lenses (I currently have a 150mm and 110mm lens in a home made lensboard from old DVD cases). It has full front movements and limited rear ones, and is great fun to use.
There was a small leak in the bellows, but the test shots came out great. (to follow).
Building cameras is much fun!

camera, roll film back and second lens

On the tripod

Interchangeable backs, pack film back shown here

interchangeable lenses, 150mm shown here

test shot of the wife