Abstract: A computer mouse input device has a housing gripped in a hand of the user with a strap member projecting from the rear of the housing to receive a finger of the user therethrough when a cursor tracking mechanism is supported on the front face of the housing so as to be arranged to receive input from a thumb of the same hand of the user. The left-click button is positioned on the side of the housing so as to be arranged to be accessible by the same finger of the user which is received in the strap member. The housing is small enough to be readily pivoted about the finger of the user between a working position in the palm of the hand of the user and a stored position at the back of the hand of the user so as not to interfere with typing when stored.