Gotta love Shin Nohara from Crayon Shin-chan running around his house screaming, "Action Bastard, ho!" in the dub.
And Rukia's response from when Chizuru (I think it was her) asked her if she liked Ichigo, her response was, "Pffft! (juice goes everywhere)"

mendokusei by Nara Shikamaru :'D

"Pantsu, Pantsu, Pantsu, Pantsu" - Chii from Chobits. xD

ooh and ofcourse the legendary sayings from Shigure from Fruits Basket xD
like; "High school girls are waiting for me!"

You better believe it!!11111


No, seriously, how did they translate that? =D

Oh and also DYNAMIC ENTRY! By Maito Gai from Naruto :''D I love it. And Konoha Senpuu but someone already said that :D

vooooooi- Squalo from Katekyo Hitman Reborn

Not an Official Anime Quote But...
 

Still just as awesome.

It came from a Naruto/Kingdom Hearts crossover 'Key Through the Heart', from one of the omakes. Naruto, who became the Keybearer in the story was fighting Jafar in Agrabah and used that 'friend summon' thing. For Gaara. Well jafar tries using his magic on Gaara, doesn't work due to the sand shield and then Gaara starts talking. "Nothing can harm me, not even your magic as different as it may be. The sand protects me, and I can kill you in an instant." He pauses "And in this endless desert? I AM A GOD!" Well you can guess what happens to Jafar. Not sure if this officially counts but another one of my favorites; this is an actual anime quote "Everything will surely be alright" from Cardcaptor Sakura. i used to know how to say it in japanese to, I had it written on the basement wall but it got covered in drywall when my mom remodeled

"Take out that cucumber! What you're doing is NOT cooking!"

Ok that one sounds hilarious xD where is it from? xD

Kodomo no Jikan Second Term, the first episode (not the OVA).