Ning CEO Gina Bianchini
www.ning.com
How celebrities help the site: Bianchini says star-studded networks on Ning have a "halo effect," that can lure users from other sites; celebs like 50 Cent, who use Ning as their Internet hub, post links to the site all over Twitter, MySpace, and other places where they have a fan base. Ning Chairman and former Netscape founder Marc Andreessen also brings plenty of name recognition to the startup.
