Oooh...Tough one. Titan A.E. and anything from Monty Oum come to mind...So I'll list my favourites from THEM.
From Titan,there's two scenes,right near the end. There's the scene where Corso uses himself as a circuit bridge,and then there's the actual creation of Planet Bob (New Earth). Both are truly magnificent scenes.
From Monty Oum...Damn,it's REALLY hard to pick. Pretty much any scene he animated for the boys at Rooster Teeth,but top honours goes to the Zero-G fight in Season 10,as well as Tex beating the everloving Hell out of Maine (The Meta),York,and Wyoming. Outside of his RT work,though,has to go to Dead Fantasy Two. The one where Tifa goes Drunken Master. Lava river. You know the one. Midair combat down the side of a tower that's probably ten kilos tall. Pure awesome.
Captcha: Easy-peasy. This choice was anything but.