I'm glad you posted this, because what you're looking for in a heroine is the same thing I'm looking for, so I'm taking notes on what others recommend in this thread.

I remember when the last James Bond movie was released a lot of the press around it was centered on Halle Berry's character, Jinx. She was being touted as the first Bond girl who was his equal, practically a female version of James Bond himself. But in the movie, she had to be rescued out of nearly every situation she got herself into. I was disappointed (but not particularly suprised) that the creators of the movie didn't seem to be able to create a female spy who really was the equal of Bond.