If you are not checking out AutoDesk Labs site from time to time, you are missing out on some very interesting developments. I find myself a month behind, but look what I found archived for April.
"ASHRAE Viewer for Revit MEP
Revit MEP utilizes the American Society of Heating Refrigeration and Air Conditioning Engineers (ASHRAE) Duct Fitting Database to lookup coefficients for determining pressure losses through duct fittings. This add-in provides a way to view the illustrations and the data table of available duct fittings from the database."
I have not tried it out, but I am downloading as I write. It is compatible with version 2011 and 2012.
I need to keep reminding myself to never stop exploring and trying new things or I may find out that I am hand drafting and the whole world went to the cloud.