The Architect...
Well, this is probably really wrong and pointless but I'll spin it anyway.
The Oracle says that the programs that are doing their jobs are invisible (obviously the Agents need a physical form for destruction and combat, but the rest of the time, 'they are no-one', floating around in the Matrix, uh, invisible, apart from Smith, who's an exile, and can't disappear any more)- the exiles are visible (herself, the Keymaker, Seraph, etc.) - but the Architect, he's most certainly a program, isn't he? H e says that "we are getting exceedingly efficient at it [destroying Zion]", so I'm assuming he's a machine/AI/a program of some sort. However, he has his own image - is this simply because he's The Architect and he can generally do that kind of thing... or is he, in himself, an exile?
~AI