over a year ago:
Hit Girl from Kick-Ass (Appropriate title) would seem to count, I think, even just from the trailers. With the Superhero catagory, I would assume that most all Comic Book ass-kickers fall under there.
If that's the case, you could include Barbara Gordon (Batgirl), Supergirl, Hit Girl as mentioned above, Angelina Jolie's character from Wanted, uhhh...
If you're set on going through with the video game genre, then Sonya Blade, Kitana, Mileena (All from Mortal Kombat), Rayne from Bloodrayne, Lara Croft, etc.