The thing about Jackie Chan is that he's, like, a complete package. He may not be the most impressive martial artist, but he does choreography, directing, and editing, and works with an amazing stunt team to create awesome action.
Anyway, most of my classic picks have been mentioned, but here's another old-school one from Gordon Liu, this time in
Invincible Pole Fighter (aka
Eight Diagram Pole Fighter). The best fight scenes always have a little bit of psychology or something going on outside of the fighting itself.
This one isn't that crazy, really, but I saw
Grosse Point Blank when I was pretty young and it's stuck with me ever since. The tone shift is ice cold.
I haven't even seen this Zorro movie, but I found this on youtube one day and thought it was great. Skip to 2:00 for the action.
For something recent, here's one from
Undisputed III: Redemption, which just came out a few months ago. Undisputed 2 and 3 put most Hollywood fights to shame with long takes, clear angles, believable hits, and no wirework. Scott Adkins is like the English Tony Jaa.
Jam it back in, in the dark.