Single word for "Private Realm"

"would also be fine with me to coin a new word". My friend is a grad student in architecture. He tells me that both students and teachers pride themselves on making up words that no one notices were just made up. lol, so my suggestion is to make something up. Maybe innercore.

Maybe just core. although not made up, it would contradict Interface well.

Things that flow well in conversation (with Interface).

• Personal Space (though not one word)
• Control or Controlled Space (from Andrews comments)
• Innerspace (as suggested by Matt)
• Intraspace (as suggested by Andrew)

But personally I like core best.

A little bit of an archaic flavor, but how do you feel about "demesne"?

This is a long shot, but how about "sanctuary?"

Granted, it would be a rather poetic use of the word, but to be honest, "interface" seems just as poetic to me.

"Innerspace?" At least it's a good movie...