Portal

On the website for the Orange Box, I spotted a movie demonstrating this game called Portal. 

Set in the Half Life world, somehow, you are a test subject who's put through the paces in an experiment involving this portal gun.  You eventually get ahold of the gun and can place two portals on the walls, floors and ceilings of the environment.  The cool thing is that you can walk, jump and see through these portals. 

I played the game through to its completion last night.  It may have been a bit too short for my tastes but I did spend about 4 solid hours playing it.  Despite that, I think they could have expanded the number of puzzles (40 or 50 would have been better) and built more upon the storyline of the game.  More about how GLaDOS was built, what went wrong and how the player's character arrived in the situation would have been appreciated.  (This was a lot like Star Trek: Elite Force in that it was a really great game but when your blood finally got pumping, the game was just about over.)

I hope a sequel is coming as this game reminded me of the old MS-DOS "thinking" games, somewhat like The Incredible Machine, where puzzle solving is the primary function.  Don't get me wrong.  You probably will be killed several times in this game but each time is 100% the player's fault.  And remember: The cake is a lie!