I'm in.
I use Rhino3D, but could certainly post up files in a format that can be opened in a variety of programs. The problem, I suspect, is that you'll find it to be rather rare that people are willing to offer up their design files. It's too easy for people to download them, and start something commercial with the file. On the other hand, if you post something close to a current commercial design it can leave you open to a whole lot of problems.
It's worth a shot, but I just can't see it being a busy portion of the site. Heck, worst thing that happens is you pull it down later
Send me a link to the swan neck photocopy. If I have time this coming week I'll model it up so the site has something better then a photocopy.
-Dave