It's a tiny little thing - quite literally tiny - but those wall outlets sprinkled throughout the house can cost a homeowner disproportionately in money and comfort during heating and air conditioning seasons. Pick an outlet on an outside wall on a cold day, particularly a blustery one, and put your hand in front of it. Surprised? There is probably a steady stream of cold air pouring in from outside , not from the prong holes in the plug, but sweeping around the junction box and through any knock...