portal
is definitely interesting.
glados is voiced by a trained opera singer, who also voices the turrets and just about every other computer voice in the game too..
what I found interesting is that she actually tried to sound like the computer herself. and while there was digital post processing over it at the end, which is really obvious in some parts... I'm intrigued to know how much was fx, and how much was just her amazing voice!
at first I assumed the sharp tone changes in her talking were fx, but now I'm not so sure!