There's also Animal Style fries that are completely different from the burgers.
"Grilled onions cooked down in the collected meat juices on the hot griddle can be added to any sandwich, and come standard if you ask for your burger or fries Animal Style. An Animal Style burger also includes extra Thousand Island spread, mustard grilled patties, and extra pickles. Animal Style fries, on the other hand, are topped with cheese, spread, and grilled onions." --Some site I found that talked about it.