the best anime fight ever

Clare vs. Priscilla (Claymore) That fight was pretty epic.

Goku vs Vegeta, both times.
Vegeta vs Imperfect Cell
Majin Buu vs Vegeta(If it's not already apparent, I'm a fanboy 😛)
Saito vs Major Kusanagi in the war stories episode of SAC.

Goku/Vegeta vs Kid Buu

any of the Kenshin fights

the Gundam battles in Endless Waltz

Mugen vs. Sara ranks high on my list.

Already a thread

http://www.killermovies.com/forums/showthread.php?threadid=396988&pagenumber=1

Jubei Chan 2: Jiyu vs Freesia. That shit is messed up.