Wormhole

A Wormhole is a fold in space-time which allows a spaceship (or person) to travel very quickly between two places that are normally very far apart. It also can allow a person to travel through time.

At the beginning of Farscape, Crichton travels through a wormhole from earth, and finds himself in the middle of Moya and Pilot's escape from the Peacekeepers. It later becomes apparent that he has the knowledge of wormhole technology in his head, something that Scorpius would very much like to have for himself.