She had Tea with Mussolini (1999) after she had taken A Room with a View (1985), then she lived in her House in Umbria (2003) and was one of the Ladies in Lavender (2004), after which she appeared in the Quartet (2012) and moved into The Best Exotic Marigold Hotel (2015), before becoming The Lady in the Van (2015).
But wait, there's more: we've just added My Old Lady (2015) to our Maggie Smith collection.
And here's the full-length movie The Missionary, courtesy of YouTube:
Welcome to the Maggie Smith fan club!