You may know Jonathan Coulton the guy who wrote that song for Portal. What you may not know about him is that the guy is a mega geek, just like us, we mean you. Just like you. And his music reflects such a mentality.
I'm generally thinking about robots and fractals all the time anyway, whether I'm writing about them or not...But on a deeper level, I think there's a thread running through many of the songs that has more to do with how it feels to be a nerd - this kind of alienation, a sense of not belonging, not being accepted.
STOP READING IF YOU HAVEN'T PLAYED PORTAL.
And ultimately, that's the story behind GLaDOS—because you find out in the final scene that, in a sense, her personality has been neutered. Even though it was done to make her less violent, that sense of rejection is there all the same.
So when you see that the cake wasn't a lie...it's all the more hitting. And when she spites you that your friend Companion Cube is gone, you wonder if she's been suffered a similar trauma.
OK, now we promise to stop talking about Portal for a while...again.
Portal: Thank you for the Music [cvg]