Although the underlying network resources needed to support virtualized networks are rapidly becoming available, the tools and abstractions needed to effectively make use of these virtual networks is severely lacking. Although networks like GENI are now available to experimenters, creating an ex- perimental network can still be a daunting and error-prone task. While virtual networks enable experimenters to build tailored networks from the 'ground up', starting from scratch is rarely what an experimenter wants to do. Moreover, the challenges of incorporating real-world users into GENI experiments make it difficult to benefit real users or obtain realistic traffic. In this paper we describe a new service designed to simplify the process of setting up and running GENI experiments while at the same time adding support for real-world users to join GENI experiments. Our approach is based on a network hypervisor service used to deploy 'HyperNets': pre-defined experimental environments that can be quickly and easily created by experimenters. To illustrate the utility and simplicity of our approach, we describe two example HyperNets, and show how our network hypervisor service is able to automatically deploy them on GENI. We then present some initial performance results from our implentation on GENI. Because our network hypervisor is itself a client of GENI (i.e., it calls the GENI AM APIs to create HyperNets), we briefly discuss our experience using GENI and the challenges we encountered mapping HyperNets onto the GENI framework.