Favorite anime episode(s) of all time

I know a bunch of you guys watch anime like myself. So I'm wondering what everyone's favorite episode of all time is in any anime.

I know I'm going to get a lot of hate for this but I love Naruto. Yeah, the most popular anime in the USA. Started watching it when it came to toonami in English and then found out how behind the english dub episodes really were and started watching in Japanese instead. Now I hate English dubs. I don't really have a deep interest in anime like a lot of you who watch Death Note, all the Gundam Series, etc, etc. But I have watched many others than Naruto so don't get me wrong.

Naruto Shippuden Episode 166 - My favorite. Not because of the action or anything but because if you've followed all of the Naruto episodes you would know the meaning of it. And the last 3 minutes with pain talking and the music playing in the background and when Naruto's eyes change. Epic. Also it starts the final fight between them.

Like I said I've watched many anime but none of the episodes of the ones I've watched hit me like that one. I do some One Piece favorites and a DBZ favorites but I'm not sure which ones yet. I've been re-watching Shippuden lately so maybe that's why I did Naruto first.

I don't read the manga for any anime so that's why I went with favorite episodes.(Although I do know who Tobi because that shit was all over the internet. Don't know the back story to how it happened though). Try to keep spoilers to a minimum, please.