Future --- Space Plane
As stated in section Air-breathing Rocket, it costs about US$10,000 to send one pound of payload into the Earth's orbit. But space planes can lower that price to US$1,000 per pound. At present, there are several experimental X-plane models in development that could make space travel as common as airplane travel. Each of these latest X-planes are resuable launch vehicles (RLVs), like the space shuttle, indicating that the X-planes can be launched into orbit repeatedly.
Air-Breathing Rocket Space Elevator Space Plane