Grimshaw anticipated that gigabit networks will make possible the realization of very large nationwide virtual computers comprised of a variety of geographically distributed high-performance machines and workstations. To realize the potential of the physical infrastructure, software must be developed that is easy to use, supports large degrees of parallelism in applications code, and manages the complexity of the underlying physical system for the user. Grimshaw's early research projects include Mentat and ELFS. Mentat was an early object-oriented parallel processing system designed to simplify the task of writing parallel programs. ELFS (Extensible File Systems) addresses the I/O crisis brought on by parallel computers. These projects laid the foundation for the creation of Legion, a collaborative project to realize the potential of the NII by constructing a very large virtual computer that spans the globe. Legion addresses issues such as parallelism, fault-tolerance, security, autonomy, heterogeneity, resource management, and access transparency in a multi-language environment. The Legion project helped set the standards for current Grid Computing research, and has also formed the technological basis of Avaki Corporation (now merged with Sybase).