Ares from the Mars trilogy may be built! Or at least a verson of it.
<i>Aldrin's hotel would be built from unused space-shuttle external fuel tanks. They are cylinders 154 feet long — about twice the length of an Amtrak passenger car — and 28 feet in diameter</i>
That's something I would like to see done. At least there is a reasonable concept to do it.
the most logical thing to develop and make. it would be a lot cheapet thn single mission launches in long term too.
By the time the thing is built there will be other means of transportation so cheap,....and usable, conveniant anough to have a go and come-back in one day