As a member of the DAR, I’ve had access to these databases, but now they are available to the public.  I actually work on two of the projects: Descendants (entering DAR application data) and GRC (indexing all names in DAR genealogy books).

You can access the databases using the following link:  http://www.dar.org/library/online_research.cfm

For detailed information about the databases, refer to Miriam Robbins Midkiff’s post DAR Databases Now Available Online.