Here is an odd "house" I noticed years ago in Falls Church, VA. Being right outside Washington and one town over from the CIA headquarters I thought it must have something to do with the them:
My wife grew up practically across the street from that house and the way it was discussed in the neighborhood was that it is/was a CIA safe house. A utility station seems much more plausible.
https://www.google.com/maps/preview#!q=320+N+West+St&data=!1...