My personal favorite, if you could call it a fight, is when Deidara first shows off his abilities.
He makes some clay spiders, drops them near some Suna guards, they crawl onto said Suna guards, latch onto their faces, and explode their faces. I laughed so hard when I first saw that.
Lee Vs madara.
Lee fodderized him with one kick!
Tayuya Vs itachi.
Never thought that itachi will lose at his own game, and against base Tayuya. ~.~