http://www.pbs.org/wgbh/nova/next/space/improbable-thruster-seems-work-violating-known-laws-physics/ I just thought this was really neat. Some dude with nothing more than a bachelor's degree in chemical engineering claims he's invented an engine which breaks the law of conservation of momentum. NASA decided to test it. They designed one they thought would work and one they thought would never work. Both achieved thrust.