This is pretty sweet. It’s behind the scenes when making The Mighty Atom (AKA Astro Boy)
http://www.youtube.com/watch?v=mxZ5H-GqouM
It is pretty good about showing the entire process from start to finish. Plus a huge retro element, since it’s all painted cells, plus the smoking animators and the clear division between the men’s jobs and the women’s jobs. But it’s a testament to how factory-like their process is that the narrator says, “it usually takes days for them to produce an episode.”
Also, this is the best picture ever:
It came from here:
http://www.youtube.com/watch?v=Xa3bX2GXAzg