Clara Shih wrote the book on social media marketing -- and now it's used as a textbook at Harvard Business School. Released last April, The Facebook Era is the bible for businesses wanting to increase their sales and consumer base through social networks. "Your customers become your fans on Facebook, and they're much more likely to be receptive to your messages than other people," she says. "So why not tap into that?" Publishers approached Shih about writing the book during her time at Salesforce, where she developed Faceconnector, the first business application on Facebook.
Shih has since left Salesforce to start Hearsay Labs, a software company that helps businesses manage and measure their online presence across Facebook, Twitter, and other social media. In the months since launching, Hearsay has seen great results, with beta clients broadening their audiences through word of mouth, and increasing their sales from existing customers by as much as 60%. The San Francisco-based startup just raised another round of capital and plans to double its staff soon. For now, Shih is doing everything she can to prepare for Hearsay's public launch this summer. "I do whatever needs to get done," she says. "Some days I feel like the janitor, some days I'm selling and closing deals." --Austin Carr