The Machine Girl (2008)
A high school girl tries to save her brother from the school bullies, but gets beaten, crippled and left for death. An engineer rescues her and restores to health, with her severed arm being helpfully replaced by a detachable prosthetic machine gun.
THE MACHINE GIRL is probably the peak of humanity's endeavours in the cinematic artform - a film so ridiculous, so violent, so inspirationally absurd and obscene that all other film makers must look at their own efforts and think "What a fool I have been, for I did not make THE MACHINE GIRL... and I could have done so". Films like this are, frankly, the only reason I have not drilled my own eyeballs out already.