Deep Space 9's control thrusters
Control thrusters were a type of propulsion technology utilized by space stations.
Shortly after the Cardassian withdrawal in 2369, Deep Space 9 had only six working control thrusters. Moving the station from the orbit of Bajor to the Denorios belt with those six would have taken about two months, so the station's deflector generators were modified to create a subspace field around the station, lowering its inertial mass. (DS9: "Emissary")
Later that year, DS9's control thrusters were used to bring the station back to its original position after a graviton field had moved the station closer to the Bajoran wormhole. (DS9: "Q-Less")