A "dot.com" company called eCircles[1,2] took exactly this approach between 1998-2001. They were later sold to Classmates[3].

1- http://www.pcworld.com/article/9704/join_hands_in_ecircles.h...

2- http://www.highbeam.com/doc/1G1-55246946.html

3- http://books.google.com/books?id=OCRdSXSKZ-AC&pg=PA131&#...