Just 2 social network pictures out of many in a PPT by Jim Moody (Duke Sociology, editor of Journal of Social Structure).
The first is a sociogram as invented by Jacob Moreno in 1930s: it depicts an attraction network in a Fourth Grade Class (Moreno was an incredible guy, for example he states that he was feeling he was God since the age of 5).
The second is a network of how vaseline (suggestions) spread. Vaseline Clinical Therapy has created its own word of mouth project, called Prescribe the Nation. The idea behind the project was to give Vaseline Clinical Therapy lotion to one Alaskan woman and to ask her to lather it on everyone she loved. In the end, 1,000 of her community’s 6,000 residents switched to Vaseline Clinical Therapy lotion (from vanksen blog).