Dual-clutch transmissions are the current Holy Grail when it comes to transferring underhood power to the wheels of the car. Nearly every automaker that does serious business around the world offers DCTs, and the ones that don't very likely soon will.
It's easy to understand the draw of the DCT: better performance and greater efficiency. But there are also problems. For instance, two clutch mechanisms mean (theoretically, of course) twice the potential repair costs, and DCTs are generally more expensive than either standard manual transmissions or conventional automatics with torque converters.
Xtrac, a company firmly entrenched in transmissions for racing applications, has developed a new technology called the Instantaneous Gearchange System, which uses a ratcheting mechanism to couple the gear hubs with the main shaft. The system has been under development for two years and has reportedly been put into race duty by multiple motorsports teams.
Apparently, the IGS technology will be less costly than other dual-clutch transmissions and could potentially be adopted by various global automakers. Hat tip to David!