The Sigma Harmonizer is a superweapon developed by FutureTech after World War III. Based on the Chronosphere project, this weapon was to be sold to the allies. However, the truth was more devious: Rupert Thornley planned to use it to not only eliminate communism, but to take over the world.
The Sigma Harmonizer is mentioned for the first time by Rupert Thornley himself. When the Soviet commander attacks the FutureTech installation in Russia, he tells the commander that his actions will mean nothing once his "Sigma Project" has been completed. When the Soviets arrive at the Sigma Island, the place where this weapon was being constructed, they had to destroy it along with other FutureTech installations, and they managed to succeed despite the many FutureTanks being built.
Even though this weapon was designed to erase the USSR from existence, it had also other functions. In the final Soviet mission, Thornley uses the Sigma Harmonizer to stop time for the Soviet forces. Basically, when the weapon was activated, Soviet forces couldn't do anything because time was frozen, but only for them. Fortunately, the weapon couldn't stay online for long and had to be deactivated after several seconds. This was still a great advantage for FutureTech in the battlefield, also because the Sigma Harmonizer becomes more powerful every time it is used, the more time the Soviets took to destroy FutureTech installations, the longer the effect of the Sigma Harmonizer will last.
The prototype of the Sigma Harmonizer was successfully destroyed by Soviet forces, however it is unknown if FutureTech still plans to build a new one, (this probably won't happen however, given the total obliteration of the device, and FutureTech's ensuing PR fallout with the rest of the world). FutureTech's leader claims not to know about Rupert Thornley's intentions and involvement, but she did not state if they were going to destroy the projects regarding the weapon or not. This weapon was, for odd reasons, not used against the Imperial rebels (although, given the fact it was in the hands of vehemant anti-communist Thornley, it probably wasn't even considered).