GamesRadar editor reckons Valve has achieved perfection:
"It has perfect... sound direction
Portal's computer-voiced guide, GLaDOS, has more of a personality than the vast majority of 'real' videogame characters. That's thanks to the compellingly scripted banter she spouts throughout. Sometimes she made me laugh, others she just confused me - once I actually felt truly sorry for her. She even made me sick with guilt about an inanimate object."