While I was thinking about the great "All These Things that I've Done" musical number in Southland Tales, I was reminded of another musical number that gives me much pleasure: the "Madison scene" from Jean-Luc Godard's Bande à part (Band of Outsiders).
If I had to call it, I would say that this is my all-time favorite movie scene, and it encapsulates everything I love about the early French New Wave films. Like many scenes in Godard's early films, it serves no real purpose in terms of plot, but it does demonstrate a joyful freedom and and resistance to conventions. And similar to Richard Kelly's choice in Southland Tales, it appears abruptly and disruptively in the film. There is a sense here that anything goes--that the old rules no longer apply--and that can be incredibly liberating. But it also means, as viewers, we are operating without the safety net that our expectations and normal film conventions provide, and that can easily lead to resistance if the experience isn't otherwise pleasurable.
However, unlike Godard's early films, this scene was intensely rehearsed and choreographed, making it seem even more out of place in a movie that looks like it was mostly improvised and shot in one take. For almost 4 minutes, the film never cuts, but that fact doesn't seem as obvious here as it does in, say, the long tracking shot that opens Touch of Evil.
And, like Southland Tales, the scene is really funny, but it could be easily interpreted as pretentious. The diegetic music cuts off (though the actors continue the dance in silence, which is one reason why the scene needed considerable rehearsal) and the narrator chimes in to reveal the characters' inner thoughts. These seem fairly consistent with the characters, until he gets to Franz. As the narrator says, "Franz thinks of everything and nothing, uncertain if reality is becoming a dream, or dream reality." While on the surface that might seem like some faux existentialist wanking, it is also completely inconsistent with Franz's character in the rest of the film. He is more than likely thinking of how Odile's breasts look in her sweater than he is about the nature of reality.
And then there's Anna Karina. She looks gorgeous, and she's clearly having fun. When she smiles, we can just relax and be in the moment without worrying about trivial matters like rules or coherence.
There's also this great moment in Band of Outsiders, where the characters decide to take a minute of silence, and the film itself participates by cutting out all diegetic sound:
It's actually only about 40 seconds of silence, but it seems like forever.