You may have already seen this floating around the various social sites such as Google+ and Facebook, but I just had to put this up...
There is an amazing live-action short floating around the internet based on the Portal series entitled Portal: No Escape. The brief movie, shown below, was directed by Dan Trachtenburg and really captures the essence of the game with a more mature perspective. Check this out and pray that this evolves into something more than just a brief clip on the Internet: