His destructive programming is taking effect. He will be irresistibly drawn to large cities, where he will back up sewers, reverse street signs, and steal everyone's left shoe.
626 was designed to be a monster, but now he has nothing to destroy. You see, I never gave him a greater purpose. What must it be like to have nothing, not even memories to look back on in the middle of the night?
In case you didn't know, the ending song Still Alive, though sang by Ellen McLain (a.k.a.: GLaDOS), it's composed by Jonathan Coulton, a part-time artist/composer and full-time geek. He has composed and interpreted numerous songs, most if not all of humorous and geeky nature.
Here's him performing the famous Portal song:
And here he is again, though this time surrounded by zombies:
You can find more songs in his site, though not all are free. Hope you enjoy them