> > "
> I recall in Larry Niven's _A Gift from Earth_, the inhabitants of the planet Plateau used specially bred worms that burrowed for specific metals, refining and excreting them.
> And while burrowing could create channels for a working fluid to reach geothermal heat sources- might as well be efficient.
If Ufog or some other generic smart-matter scenario, ever becomes common then probably much matter that is not being actively used will be held in common. Ufog-rentum?