In a manually movable computer mouse with a mouse movement sensing system for providing mouse movement signals, and at least one user finger operable control switch, for providing control signals for a graphic user interface, the mouse has a boomerang shaped body ergonomically shaped to fit and support the user's hand in a naturally relaxed curled hand position, with a main body portion and a narrower neck portion extending at an angle of about 45 degrees to 90 degrees to the main body narrow enough to be interposeable between the thumb and first finger, and with an integral mouse movement control fin or tab extending above the mouse body and being thinly shaped to fit in the relaxed space between the first and second fingers (and to also provide an alternate pen-like grip between the thumb and first finger) to orient the mouse to the users hand and move the mouse with user arm movements. An integral wrist support may be provided extending from the wrist end of the mouse. The movement sensing system is adjacent that same end.