The title of this paper immediately brings to mind images of a harmful technology that would change the operation of the Internet. In this case, the term disruptive is used to describe a way to revolutionize the Net and break away from the old adage, "If it's not broken, don't fix it." The proposed technology to accomplish this task is overlay networks. The paper describes the characteristics of overlay networks that make them highly adaptable and well-suited to encourage innovation. PlanetLab is then introduced, which serves as a testbed for overlay networks. The overview of PlanetLab offers a glimpse into what could eventually be realized on a much larger scale.