It's not been a good year for high technology delta-winged white transports. NASA's still scratching its head over what went wrong with Columbia -- they thought they'd found a protective plate drifting away from the craft on radar images from day two in orbit, but the darned thing turned up in the wreckage. So the tiny fleet remains grounded, leaving its passengers stuck with older, cruder alternatives. As has happened with Concorde, whose retirement date has been set today for six months hence. All very sad for my inner (OK, outer) child, who watched the Apollo missions and the early days of Concorde with the fervent hope that he'd be flying hypersonic jetpacks on Mars by the time he was twenty. Now all that history will be consigned to museums, icons of a very different age, beautiful experiments that finished in dead ends. The money ran out. That's OK. Look ahead. A study claims that there is no theoretical reason preventing a working space elevator -- at its most basic, a cable connecting a geostationary satellite to earth with cars crawling up and down. Build one of those, and the cost of putting stuff in orbit reduces to a fraction of the current costs. As this is the most expensive part of any journey within the solar system, the economics of getting ourselves spread around the place change dramatically. The cost of such an elevator? Around half of NASA's annual budget, and less than some other engineering projects such as the Gibraltar Bridge. It's not just a matter of sending up a large reel of Belkin's finest stranded-core Cat5 and unwinding it, of course. The cable has to be incredibly strong -- the required tensile strength is within the theoretical range from carbon nanotubes, but much more than anyone's actually been able to make. As you can imagine, they're working on that with some eagerness. There are other issues such as safety: the idea of an unstoppable cheesewire wrapping itself around the equator is not one to be taken lightly. Powering the crawlers is another issue, but there are plenty of ideas for that. The enthusiasts say it'll be practicable within ten years, which seems a little optimistic. But then it took just eight years from Kennedy's "We choose to go to the moon" speech (well worth watching, for many reasons) to Armstrong's small step for man, roughly the time it takes London Underground to fix an escalator these days. Sadly, it is harder to imagine Tony Blair making such a speech -- even though it's well within our national means and the benefits would be enormous, over a long period -- than it is to conceive of the project itself. But my inner child insists we try.