Ancestry.com and Facebook app
Living descendants can give each other helpful information about ancestors, and can encourage each other to do just a bit more research to break down those brick walls. The conversation about the past is one of the reasons the hobby of genealogy is booming.
In addition, those who pursue genetic matches always have to begin with the living match, and need to find an ancestor in common from there. By making the connection to the living match fun, social, and appealing, as it may be on a social network website, it may all become a bit easier to begin the conversations that will help identify common ancestors.
Also published on my Genealogy Trends blog