I'm inclined to say Shepard from Mass Effect but that wouldn't be exactly fair as the character is tailored by player actions and has the potential to be thoroughly unlikable (albiet she's always a strong female lead, which is a plus).
On the note of BioWare, there is however Bastila Shan (Same voice actress, too!) in Knights of the Old Republic, and on the note of Star Wars there's also Jan Ors in the Dark Forces saga (How often do you get a female love interest in a game who makes a habit of saving your ass rather than follow conventions?).
Top favourite might have to be Cortana though. I can't really say why, there's just something about the character as a whole. Voice acting, the fact she's actually helpful and has good writing behind (most of) her dialogue, it all meshes together into a very likable character. Pretty, too.
On the note of BioWare, there is however Bastila Shan (Same voice actress, too!) in Knights of the Old Republic, and on the note of Star Wars there's also Jan Ors in the Dark Forces saga (How often do you get a female love interest in a game who makes a habit of saving your ass rather than follow conventions?).
Top favourite might have to be Cortana though. I can't really say why, there's just something about the character as a whole. Voice acting, the fact she's actually helpful and has good writing behind (most of) her dialogue, it all meshes together into a very likable character. Pretty, too.