Portal came out in 2007. I've owned since around then, but only got around to playing it recently. What a hoot! Both hilarious and ominous throughout, the tone of the game is captured nicely in the ending song, sung by the computer as the credits roll.
A bit of backstory: You are a test subject in a research lab that is being run by a slightly psychotic computer. It's trying to be helpful, but it becomes fairly clear that at the end of the experiment, you will be killed (through a process which turns out to involve an incinerator and something called "your victory incandescence"). Throughout, the computer promises you cake if you succeed (despite occasional scrawled messages from previous experiment participants which read "The Cake Is A Lie!"). Aperture Science is the company that owns the testing facilities; they are linked to Black Mesa, the ultra-evil corporation of the Half-Life universe.
This is the final theme song, which is ominous because (a) there are veiled threats to the fate of humanity and (b) you have just finished incinerating all of the computer's modules, yet here it is singing you a goodbye song. I really enjoy the song, and just now discovered that it was written by Jonathan Coulton, who also wrote such Murray Favourites as Code Monkey, Creepy Doll, and Skullcrusher Mountain. I think you can probably enjoy it even without having played the game.
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