Potential commercial applications include any micro and nano-satellite missions that would require precision thrust, drag-free flight or incondensable propellant. Terrestrial applications for the micro RF ion thruster include a micro machining and semiconductor fabrication by nano focused ion beams. The microvalve has many applications where precise control of micro flows is required. The miniaturized valve has potential in many ion engines including small Hall effect thrusters as well as gridded ion thrusters, miniature chemical thrusters typical of ACS or mini spacecraft propulsion. The CNTFE cathode has already shown applications in the colloid propulsion system Busek delivered to JPL in 2008. In addition, Busek is investigating CNTFE cathodes for terrestrial applications. Applications of micro RF ion engines include many currently planned and future NASA missions that require precisely controlled and highly throttle-able thrust for formation flights. These missions include Laser Interferometer Space Antenna (LISA), Space Interferometer Mission (SIM), Submillimeter Probe of the Evolution of Cosmic Structure (SPECS), Space Astronomy Far Infrared Telescope (SAFIR), Terrestrial Planet Finder (TPF) and Stellar Imager. Furthermore, micro RF ion engines can serve as tip-off control for formation flying satellites. Not only applicable to formation flight applications, micro RF ion engines are also the prime candidate for missions calling for zero drag. Zero drag can be achieved by varying thrust to counter the drag force measured from minute deceleration of the spacecraft. The thrust must be rapidly responsive and precise, which are the special features of RF ion engines.