1. A method of providing cooling to electronics, the method comprising:providing a chassis to house circuitry, the chassis having a first and second surfaces, and an air inlet;
providing an airflow moving device to create an airflow in a first direction that is communicated to the chassis via the air inlet;
providing a wall structure including:a height that extends up from the first surface towards the second surface to form an elongated opening between a top surface of the wall structure and the second surface;
a width that is solid but for a wall aperture through the width of the wall structure to allow through-flow of air in the first direction; and
a length that extends across a width of the chassis and is substantially perpendicular to the first direction;
providing a louver connected to the wall structure to close the wall aperture in response to the airflow on the louver being above an airflow threshold and open the wall aperture in response to the airflow on the louver being below the airflow threshold; and
enabling the air to flow over the top surface of the wall structure through the elongated opening.