Not sure if this will be of use to anyone else, but (like the Article Database) since I'm putting it together I might as well put it up for others to utilize.
As I read through the book mentioned in my last post, Animation Art by Jerry Beck, I'm putting together all the films mentioned in the book into YouTube playlists. I guess even if you're not reading through the book, this could interest you just to see important films in animation's history.
These aren't all the films mentioned, just the ones that I felt were important enough to look up. Also, a few more obscure films weren't on YouTube, but on other sites like Dailymotion. I didn't compile those into any list, I just looked them up separately.
I'll be adding to this as I make them: