Landing the first stages

I am always surprised how conceptually simple most really good ideas are.

The cost of the energy required to get to space is cheap. Perhaps even as cheap as $1 a pound. The problem is that the cost of hardware needed to get to space is really high. If you had the equivalent of a 747; something you could take off to space, refuel, and quickly take off again space travel would be cheap.

A lot of ideas I have seen are simply trying to get a single vehicle which can get to space like a plane. This might be possible, but has thus far been really difficult. There might be an easier way though. Make a multi stage rocket, but make the stages which drop off into drones. The drones could then land, be hooked back together, then launch again.

SpaceX is trying to do something similar to that. So far the tests haven't gone all that well, but given how well a lot of their launches have been going I expect those details to be worked out quickly.