How can I edit the contextual menu in Ubuntu? How can I add/remove items? Will the method for Ubuntu also work for variants such as Kubuntu/Xubuntu/Lubuntu? Is there a configuration file that I can edit, or do I have to use a program/utility instead?
Edit: Someone pointed out that every program handles its own contextual menu. In particular, I would like to be able to edit the contextual menus for Nautilus and the Unity desktop interface.