As anyone who has scanned a phone bill knows, telecom companies don't like to make things easy. One Source Networks is different. The company, which builds and manages data and voice-over-Internet-protocol networks for large companies such as Intuit and ClearChannel, provides a single source of contact—and a single bill—for clients' telecom systems, regardless of how many carriers or vendors are actually involved behind the scenes. "We become the single throat to choke to make our customers' lives easier," says Ernest Cunningham, who founded One Source in 2006, after his previous employer, Broadwing Communications, was acquired by Level 3 Communications. Cunningham attributes his company's success to increasing demand for cloud-based applications and VoIP services, which require increasingly sophisticated data networks.