Poll: Which set of siblings played by the same person is done best?

There is a unique set of technical problems when using the same actor for two roles... things like split screen camera work and making sure each sibling has a unique personality. You can see some of what goes into it by watching this behind-the-scenes video: http://www.youtube.com/watch?v=c03GVRmmTL0 Which set of siblings played by the same person is done best? Discuss the list here.