Between TRON: Legacy and Oblivion, Joseph Kosinski has put together the two most beautifully designed films I've ever seen.
But what fascinates me most about Oblivion is the Sky Tower, especially the spindle it sits on.
Kosinski readily admits that it could never be built with today's technology, because what kind of material could you make the spindle out of? Think about it: 3,000 feet long and a couple of feet thick, yet remaining so strong as to support an entire house and, more importantly, so stable that the water in the swimming pool doesn't slosh!
There's only one way that I know of to accomplish this.
Two words: Stasis Field
The Variable Sword used in Niven's Known Space stories is a length of monomolecular wire held rigid by a projected stasis field. (There's a little red ball at the end of the wire so the wielder can tell where the otherwise invisible "blade" ends.)
What say ye, O-Deckers?