Ok: so the game "Portal" is an epic, epic piece of beauty and genius that deserves to be played by everyone.
It is, at once, scientific, genius, and makes you feel like you're in a first-person shooter even though it's actually just a huge puzzle where you never hurt anyone (except for small, apologetic robots)
It is from this game that the world derives the wonderful phrase:
"The cake is a lie."
Furthermore, once you beat the game, the woman robot voice (who you're trying to obey/discover/destroy for the entire game) sings you a little song at the end.
Note: Before the ending credits, you've just beaten the main robot lady computer thing. But seriously, the game SINGS to you! And it's ADORABLE!
But there's no sense crying over every mistake,
you just keep on trying 'til you run out of cake!
And the science gets done, and you make a neat gun,
for the people who are still alive.