i think it'l be a while before someone even comes up with a plausable FTL engine
THEORY!
nasa's latest addition to scramjet flighttests spells good things for spaceflight
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. engines with that kindof speed and efficientcy (it's very efficient iirc) like that may one day enable horizontal launches.
remember the weight of fuel is one of the biggest reasons reaching orbit is so hard to do (and thus expensive).
ie: fly horizontally, just like a normal plane, then pitch up, hit the scramjet, pick up insane speed, and you may have enough inertia to reach, or even break orbit.
this equals WAY cheaper orbit/spaceflight.