The Eye: what was it?

[Alfirin]

That actually sums it up quite succintly. Saron's gaze and will is his All-seeing Eye, much as the force of his armies is described as his hands and fingers. Though I do still hold deep in my heart that the eye in the mirror if not Sauron's literal eye resembles it in apperance, he must have gotten the idea for the shape from somewhere.
Your comments of Saruman actually also works. Much as Saron desired ultimate order and personal control of the world (all under my All seeing gaze). Saruman, at least intially professes to wanting to rule the world becuse he thinks it needs his and the other wizard's guidance i.e. a "guiding hand" As for the WK symbol, well, his current residence did used to be called the Tower of the Moon, and the Moon has always been associated with Magic.

One final aside, just to satisfy my own curiosity. Would most of this forum agree that, inaproppriate and undesirable as Peter Jackson's depiction of Sauron is, its still light years better than the way he was shown in the Rankin Bass Cartoon, I mean what was that, a compass rose?, a sixteenth century chart of the sun and ther planets??