Another princess is Cindy Collins in Zoom: Academy for Superheroes. Bonus points given that at one point she actually wanted to wear a pink princess outfit, with pointed hat with tassel included, as her combat uniform.
Last Action Hero, where Jack Slater's teenage daughter subdues a mook in her bedroom with her bare hands and hardly breaking a sweat, all the time faking sounds of anguish and pain to keep his fellow mooks from interrupting.
Jason Lane from Superman Returns manages to throw a piano when Lois is under imminent threat.
Raven in Cecil B. Demented. She's one of very few sprocket holes who escapes the police alive at the end, and in the beginning she punches a guy out.
Zoe Bell. Described in the script for Death Proof as "Cute-as-a-bug's-ear Kiwi stuntwoman". In one particular moment, she beats Stuntman Mike with a six-foot steel pipe she picked up off the side of the road, while he's still in the car.
Maruti in The Return of Hanuman is a little boy who is very strong and able to lift a house. It's justified since as the title of the film suggests, Maruti is the reincarnation of Hanuman, a Hindu god.