Abstract: A support shelf amounts on a computer monitor for supporting multi-media speakers or other office related items above a horizontal work surface. A base positively locks to an upright in one of a plurality of angularly adjusted positions which allow the upright to support the base horizontally on a titled monitor. The upright has a mounting plate which attaches to the top of the monitor and supports a panel which extends vertically along the side of the monitor. An adjustment plate extends perpendicularly from the bottom of the panel above the work surface and has an inverted V-shape with a flange extending from each side thereof. The base has a square-shaped support surface with a top lip to prevent the speaker or other items from sliding off of the shelf. A bracket is formed with a plurality of horizontally aligned spaced channels on the bottom of the base for receiving the adjustment plate to mount the base to the upright.