You’ve read all of your free items this month. To register, get added benefits and unlimited access to articles, Become a Member. Already a Member? Sign in. Advertising Age Article Abstract Spotting the Creators of Peer Influence Here's How to Find the People Who Generate 500 Billion Impressions a Year By Josh Bernoff, Published on April 20, 2010 9 Want more Access, Content & Connections? Upgrade to Membership. We are glad you are enjoying Advertising Age. To get uninterrupted access and additional benefits, become a member today. Register Now Already a member? Log in.