Martin Varsavsky's fans see him as a rebel who has often disrupted the telecommunications industry. An Argenti...ne/Spanish entrepreneur who has launched seven companies in the past 20 years, Varsavsky's current venture is FON, which he describes as a "community-empowered company dedicated to building the world's largest global WiFi network." He has a few partners helping him get there -- Skype, eBay and Google. In a podcast interview with Kevin Werbach, a professor of legal studies and ethics at Wharton, Varsavsky discusses how he invented the "call back" (a cheap way of making international phone calls), the differences between American and European technology companies, and several other issues.