Apple Patents: Optical Touch Pad Mouse?
MacPlus.org (French) notes a relatively new Apple Patent (Filed Sept 2002):
A peripheral input device for controlling movements on a display screen, the peripheral input device comprising: a housing; and an optical touch pad carried by the housing, the optical touch pad being configured to translate finger motion into movements on the display screen.
Essentially, the new patent appears to be for a mouse with touchpad in place of the button. This appears to be an update to a previous concept patented by Apple -- the rotary mouse.