The most magical is the space elevator. Mundanely speaking, launching from high-altitude planes or balloons, and using space planes, could save a lot of fuel,

The most magical is the space elevator. Mundanely speaking, launching from high-altitude planes or balloons, and using space planes, could save a lot of fuel, as well as allowing for a wider selection of launch sites and, as a consequence, wider launch windows and the ability to change where one launches from at short notice, all of which could help reduce launch costs.