3. C-3PO ('Star Wars')
Basic Function: Constructed by a young Anakin Skywalker, C-3PO exists solely to help humans and other living beings at whatever they desire. That can be doing manual labor around a house or helping overthrow the Galactic Empire.
Good or Bad: If you are opposed to the Empire and its evil means, C-3PO is certainly a force for good. Your average stormtrooper might have a different take on the situation.
Boldest Action: Finding a way to convince the Ewoks to join their quest to overthrow the Empire.