Virtual wind tunnel for MacOS X?

Hi,

I am trying to find out what software there is for MacOS X that would
allow me to perform virtual wind-tunnel tests given a 3D shape. At the
moment I am having a little difficulty doing so. If there is one that
uses X-Windows and compiles for the Mac, then that would be good too.
Otherwise one for Linux (PPC preferebly) or MS-Windows would be ok, but
MacOS X is what I would really like.

At the same time, I would be interested in any projects for non-virtual
desktop wind tunnels. Also, does anyone know how I would go about
fabricating a real object based on a 3D design?

Tarken