Newbie Question

How could I do this idea: http://www.instructables.com/id/Add-a-rapid-fire-button-to-your-mouse-using-a-555-/step3/Connecting-the-circuit-to-your-mouse/

To a mouse with an arduino Uno.

All I like here is the idea, the button doesn't have to be in the mouse or anything I am just wondering how I could produce mouse clicks from the mouse and using the arduino's code to do so?

Are you double posting

http://forum.arduino.cc/index.php?topic=445908.0