For those of you looking at getting into 3D printing, Autodesk labs is now offering a tool to automate the export of a Revit model to a format read by 3D printers (STL). The tool that is being offered works with all the flavors of Revit (Revit Architecture, Revit Structure and Revit MEP). Here is a short clip from their site:
"STL is a popular file format for stereolithography used for rapid prototyping and computer aided manufacturing. An STL file describes the surface geometry of a 3D object. "
You can download here: http://labs.autodesk.com/utilities/revit_stl
or visit the Autodesk labs site at: http://labs.autodesk.com/