But, I think the title that has left the biggest impression on people, and the one that I have enjoyed the most is Portal included on Valve‘s The Orange Box. A first-person puzzle game built around the titular portal device, the user is a subject in an experiment who must maneuver through a series of increasingly-difficult rooms. The graphics, while not mind-blowing, are sufficient while the sound design is absolutely brilliant. The computerized voice guiding you through the experiments is wonderfully kooky.

So if you haven’t played Portal, go pick up your companion cube and get at it. (the rest of The Orange Box ain’t bad either)