In 2006, New Scientist magazine published an article titled Relativity drive: The end of wings and wheels1  about the EmDrive [Wikipedia] which stirred up a fair degree of controversy and some claims that New Scientist was engaging in pseudo-science.
Since the original article the inventor claims that a "Technology Transfer contract with a major US aerospace company was successfully completed", and that papers have been published by Professor Yang Juan of The North Western Polytechnical University, Xi'an, China. 2
Furthermore, it was reported in Wired magazine that the Chinese were going to attempt to build the device.
Assuming that the inventor is operating in good faith and that the device actually works, is there another explanation of the claimed resulting propulsion?
1. Direct links to the article may not work as it seems to have been archived.
2. The abstracts provided on the EmDrive website claim that they are Chinese language journals which makes them very difficult to chase down and verify.