An introduction to the Inventor Mesh Enabler from Autodesk Labs
The Inventor Mesh Enabler is a free (But time limited) technology preview that enables Inventor users to work with imported Mesh data.
As shipped Inventor 2012 can import mesh data from Catia, STL and JT files. The Mesh Enabler for 2013/2012 adds the ability to post process the imported mesh data to convert the mesh features to Inventor Base features.
Find out how it's done in this quick tutorial.