Guess it goes to show that you can live with just about anything and eventually pay it no mind...
Something has died in the wall. In this wall to be exact:
That's our exterior walls-- the perimeter of our house is 2 1/2 brick thick all the way around. Something small, but powerfully stinky, has wedged its way into some crevice and is now stinky pantsing the place up. We had taken off this piece of front door trim to repair a section of the door jamb and just haven't gotten around to putting it back.
So if you sit on the couch for more than a moment, you get waves of stench as the air wafts through the wall, out of this opening and into the room.
Mmmm.