How do I remove a GameObject var?

If this is my script, how do I remove the game object? I need to rephrase though. How do I remove it from the property window? When I click on whatever the script is in, the game object will want me to assign something to it. So I do. Now how do I remove that game object from that spot? Also, how do I add one to it? I will answer all answers hopefully in less than an hour after posted if you have a question.

var Product : GameObject;

To delete an item, either click the selector and select “none” from the list, or press the delete key. To replace an item, either click the selector and select another item from the list, or drag’n’drop another item on the slot.