Over at ARCxl, you can download a bunch of Revit details for free.  According to the website, these details were all created natively in Revit.

The Terms of Use describes the proper way that these details may be utilised, and you must agree to these terms when you register. 

Effective July 19, 2011, two very significant alterations were made to the ARCxl website. We have added CAD/dwg, and PDF file formats to our library. We have also removed restrictions on account location and email address types.

Quoted from
ARCxl for Revit: ARCxl adds CAD/dwg, PDF and Eases Restrictions

 
Upon downloading a detail, you must also agree with this popup:

By clicking CONTINUE, I confirm I have read and agree to the ARCxl Terms of Use in their entirety. I agree to hold all liability for the use, review, compliance with all applicable laws, codes, and ordinances. I agree to seek professional review by an architect or engineer, and that ARCxl details and components are provided as-is without warranty of any kind. I understand that this is a single-use license and not a transfer of title.