This year NASA's Institute for Advanced Concepts (NIAC) has selected a dozen new-fangled ideas that could lead to revolutionary changes in the way we explore the near and far solar system. Among these advanced concepts was a proposal headed up by Dr. Gerald A. Smith, of Positronics Research LLC, Santa Fe, N.M. whose "Positron-propelled and Powered Space Transport Vehicle for Planetary Missions" could lead to the kind of high-efficiency propulsion systems needed to get there and back without having to cart vast quantities of chemically-based fuel and oxidizer along for the ride.