NOVELTY - The apparatus has a support unit for supporting a planar desktop surface e.g. no-skid surface, of a desktop (1) in a horizontal position while mounted on an exercise equipment e.g. treadmill. An adjustment unit expands an overall width of the apparatus, and allows the overall width to be selected and set. The units are set in selected positions. The desktop surface includes a pen/pencil cavity (10) of suitable size to receive a pen or pencil. Eyelets (7) allow the apparatus to be tethered. One of desk legs (4) of the support unit is coupled to a widthwise side of the desktop.    USE - Portable desktop apparatus for an exercise equipment e.g. treadmill, exercise bike and elliptical machine and for accommodating a laptop computer or other equipment.    ADVANTAGE - The apparatus is easily and stably mounted to a piece of standard exercise equipment and is set at a position desired by the user. The apparatus is lightweight, adaptable, adjustable, made of durable material, and easily broken down for transport. The apparatus allows user to mount the apparatus to exercise equipment such as treadmill in order to benefit from light exercise while conducting work-related tasks or other business. The apparatus allows user to receive health benefits as a result and to bum calories while working as opposed to working in a stationary position and having to find other time for exercise or forfeit the opportunity to exercise. The apparatus is equipped with safety features for improved stability. Proper use of the apparatus provides long-term health benefits for users. The apparatus enables the user to conduct computer activities or write messages while communicating with associates telephonically, while burning calories and improving fitness due to simultaneous exercise. The apparatus is sufficiently portable to allow user to pack the apparatus away in a suitcase or briefcase and travel with the apparatus. The apparatus allows the user to fix the apparatus to their home exercise equipment in a more permanent fashion. The apparatus is equipped for easy setup and breakdown in order to maximize the time management benefits conferred upon the health-conscious user.    DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for a method for using a portable desktop apparatus comprising a step of mounting or affixing the apparatus to an exercise equipment.    DESCRIPTION OF DRAWING(S) - The drawing shows a top view of a portable desktop apparatus.    Desktop (1)    Desk sides (3)    Desk legs (4)    Raised lip (6)    Eyelets (7)    Pen/pencil cavity (10)