Just remembered my recent favorite, from Disney’s Fantasia: Firebird.
Two parts give me a bit of a jolt down my spine every time I watch it:
The lava creature’s eyes snapping open at 2:45, and the rejuvinated dryad’s expression of, um, exuberance at 8:44.
[Nitpick]It’s from Fantasia 2000, not the original Fantasia.[/Nitpick]
I thought of this one, too. It definitely produced tears in my household.
Nevermind. I was totally wrong.
Another one for Rejected; until I’d seen it, Billy’s Balloon had been my favorite.
I was pretty lucky to have seen Billy’s Balloon, Rejected, and Hertzfeldt’s three-part Welcome to the Show/Intermission in the Third Dimension/The End of the Show theatrically in animation festivals; the audience reaction to each one amplified just how funny I found them. I bought legal DVDs of them, too (they’re notorious for being heavily pirated), with Rejected having wonderfully insane packaging and disc labeling on its stand-alone disc, and Billy’s Balloon and Welcome to the Show/Intermission in the Third Dimension/The End of the Show were on the DVD The Animation Show, Volume One.