They are large (males tend to run about 160-180 lbs.) but gentle, sweet and lovable. They are loyal, and while they are generally well-mannered, they are also fiercely protective of their families. They shed and drool, so if that bugs you, don't get one.
Famous Newfs: the original "nanny" from Peter Pan (Disney made her into a St. Bernard), and Seaman, the dog that helped lead the Lewis and Clark Expedition.