Tantalus field

From Memory Alpha, the free Star Trek reference.

In the mirror universe, the tantalus field was a 23rd century device found aboard the ISS Enterprise, which could be used to monitor and eliminate enemies from existence with the touch of a button.

Captain James T. Kirk owed his success against a number of enemies to the tantalus field, and the unknown alien scientist whose lab he plundered for it. The field was apparently a secret from everyone except Marlena Moreau, and to others it seemed that Kirk's enemies had a tendency to "simply disappear." The field was used by Moreau to save the "original" Kirk when he was trapped in the mirror universe. (TOS: "Mirror, Mirror")

In a story planned for an unrealized William Shatner guest appearance on Star Trek: Enterprise, it would have been revealed that the Tantalus field did not kill its victims, but transported them to a different time. In the story, it would have been revealed that, sometime after the events of "Mirror, Mirror", Mirror-Spock had used the device on Mirror-Kirk, depositing him on a remote planet in the 2120s, where he would have later been discovered by the crew of the NX-01 in the 2150s, shortly before the alternate timeline of the "Mirror" universe was to have diverged from the standard Trek universe.