In 2003, Swedish businessman Niklas Zennstr?m sent out an email message to his friends, asking them to take a look at a new Web site called Skype.com. With that message, he launched one of the most popular Internet services of the early twenty-first century. Skype revolutionized the way that people communicated by offering free and low-cost phone calls to anywhere in the world through the Internet. In the years since Zennstr?m sent that e-mail message,...