[numpad0]

Could it be Google+? 3 of 3 my Gmail addresses associated with their profile in some way were on it. Two of it I might have used to register a domain, but the last one I used for G+ and one other website only and none of any friends know this. Also I'm not in US or have US background, can't be from American friends' phones or retailer CRM.

[onefuncman]

This seems like a winner to me. Iterating a graph along some association explains the ordering mentioned in the blog post, and explains the breadth of connectivity.

[anoncareer0212]

shocked to read this, you can immediately rule it out after reading the article or looking at the sample data

[Jaxkr]

It’s covve, a free personal crm app