[adrianN]

Since the main difference between sand and Intel processors is some expensive processing, processors might have a fair price of, to be generous, 1000 times the cost of sand. So processors cost the ballpark of $10 per kilogram.

Obviously they don't right now, but it gets you thinking about the intrinsic value of processors and how that price might move in the future.

[SideburnsOfDoom]

Quite right: it is indeed moving that way and it's worth thinking about.

See for instance http://www.antipope.org/charlie/blog-static/2012/08/how-low-...