3D Printing & Revit

In college, we had access to a 3D printer that could build a physical model of our drafted CAD model by spraying corn starch--or some other medium--layer upon layer.  It looks like we will be able to download a free Autodesk program to convert our revit files to useful format (.stl) for 3D printing (or Stereolithography) should we ever want to make a 3D model for a client or the CT Engineering display case.  Here are some really cool large buildings modeled: http://www.materialise.co.jp/mammoth-stereolithography

After a quick google search, it appears www.makexyz.com  has some local Seattle shops that will build a model for a price per cubic centimetres ($0.25/cm3 to $1.00/cm3).  Based on some typical assumptions, I think that would could model a 2500 sq ft house at 1/8"=1'-0" scale for about $220 (at the low end of prices).