Innovaya Composer for Revit

Innovaya Composer for Revit is an add-on program for Autodesk Revit Architecture, Revit Structure, and Revit MEP . It imports the Revit design element information into Innovaya project model and exports the model into an .INV file, which can be read by all Innovaya applications, including Innovaya Visual BIM, Innovaya Visual Quantity Takeoff, Innovaya Visual Estimating, Innovaya Design Estimating, and Innovaya Visual 4D Simulation.

There's more information on the Innovaya website (although the page link only indicates support up to Revit 2011, Innovaya's homepage has a blurb about Revit 2013 support).