Anyone who has an updated copy of Portal 2 on Steam you should fire it up now. I dare you. Warning: Spoilers inside! For this who don't or can't be bothered, this is why: An exceptionally creepy new intro. I fired up Portal 2 in good faith last night, wasn't expecting it and I had a bit of a Moment. Apparently it's on DotA 2 too. If you don't play a lof of Valve games you may not get it.