If a ship moved rapidly around a black hole it would experience half the time of people somewhere else. The crew however, would have to travel near the speed of light for this to work.
Speed of Light
Light does not experience time. Which means if you accelerated the speed of light you would not age, while everything around you did.
Predicted by the theory of general relativity; would create tunnels in space-time. However, they would collapse very quickly & only be suitable for small particles.