Electric Space Propulsion - Research carried out by the Institute of Space Systems. Also contains a good overview of the various types of electric propulsion.
Electric Spacecraft, Inc. - A network for researchers of electrodynamic field propulsion techniques for space travel.
Hall Thruster Experiment - Princeton Plasma Physics Laboratory. This site documents the undergoing research in electric propulsions.
How Electromagnetic Propulsion Will Work - Illustrated tutorial shows how Goodwin's electromagnetic-propulsion system works and how it could send spacecraft deep into space.
Mini-Magnetospheric Plasma Propulsion - An advanced plasma propulsion system that will create a large scale magnetic bubble around the spacecraft to ride the solar winds.
Tethers Unlimited - Use of space tethers for propellantless electrodynamic tether propulsion, pumped tether length propulsion, and transferring energy and momentum from one spacecraft to another.
Xenon Ion Propulsion - Description of Boeing's commercial XIPS (Xenon Ion Propulsion System). Designed for satellites, but a specialized version of it was used on NASA's Deep Space 1 spacecraft.