"Uh huh, thats cool. I pump like fifteen thousand bullets into him and then he can just come over and stick his sword up my butt. That's fair, I'm so glad this is so balanced." Or something to that effect. And I talk to myself always, unless there are people around. Also when I do math I say the calculations out loud, not that that's relevant.
EDIT:Also, "That's right you little *****, I just threw a huge sword at you from a frickin hundred meters away." Also in place of that, "Nice Catch, hehehehe." And "A little left, a little left, BOOOOM HEEAAADDD SHOT! SUCK IT, IM A BETTER SNIPER THAN YOU!" Or "Damn nice shot, (insert name here), just wait til next time." And the occasional "Ohhhhh, that had to hurt"