An Earth-to-orbit elevator (sometimes called a "Beanstalk," a "space bridge," or an "orbital tether") is one of those ideas that, at first blush, sounds almost too ludicrous to be real. After all, we're accustomed to thinking of rockets as our only way into space, mixing danger and adventure; taking an elevator into space sounds almost boring. It turns out, however, that a space elevator is not only plausible, it's potentially revolutionary. Perhaps more importantly, given all that has happened in recent days and weeks, the notion of a space elevator can provide a bit of almost giggly optimism about the future.
We're already cranking out ribbons of carbon nanotubes. No, they're not quite strong enough for the job and we can only produce a few feet per hour, but we're getting there. In fact, I'd argue that we're making more actual progress toward a functioning space elevator than we are toward sending humans back to the Moon.
It's a quiet revolution, which makes it all the more interesting to watch.