Have you ever thought about this “universal car” that can transport a person from point A to point B in literally any mode? The universal car can run in any medium – land/surface (road, rail or all-terrain), air (fly) or water (swim the surface or submerged) or even vacuum/space (like a spacecraft).
Let us say you are in Sacramento and you get in the car. You just say ‘take me to New York by air’, and it flies the car right from your garage to New York. There, you say ‘take me to London, England by water’, then the car simply swims across the Atlantic to get you to London! Then you say take me to NASA’s permanent space station, and the car simply goes skywards 100 miles into space. From there, you say drop me back to Sydney, Australia, and you descend back to earth at Sydney harbor! From there you say, take me to Siberia, and the car takes you by air, water, road, rail and all terrain to Siberia, Russia. From there, you say fly me home, and the car flies you right back to Sacramento!
The car chooses its own fuel (gasoline, electric or jet fuel), its own propulsion system (engine, body shape, motor, wings, fins, wheels) and its own mode/route/path (land/air/sea/space, shortest path, etc.). As the passenger, all that we have to do is specify the destination! Such is the universal car that I imagine will happen one day!