Chiu Chi-ling (b. 1943), a martial arts instructor and actor, who played the Tailor from Pig Sty Alley in Kung Fu Hustle (2004).
That's right: this man was 61 years old when he kicked the Black Axe Gang's collective @$$!
Taught Huang Gar kung fu by his parents from the age of six, Chiu opened his own school in the early 1970s. He came to the attention of the Hong Kong film studios, and they came calling. Chiu started working as an actor and stuntman in 1978, and has appeared in over 70 movies since. Some of the big names he's worked with include Jackie Chan, Jet Li, and Stephen Chow.
At the same time, he still oversees his two schools - one in San Francisco, the other in Hong Kong - to ensure that his parents' Kung Fu skills are being passed on to new generations.