Tokyo Godfathers is one of the best Christmas movies out there.
The film follows three homeless characters as they try to return a lost baby to its mother, and manages to expand on each of their personal stories throughout one miraculous night. By the end of the film, I was rooting for our "bum, queer, and runaway" as they explored the city, stumbled through a series of crazy coincidences, and rediscovered what their families mean to them.
Every Satoshi Kon film i have seen has made me wonder why I hadn't gotten around to them yet. His films ooze humanity, with well developed characters and fleshed out worlds brought to life through great writing and fantastic animation/art.