2014.06.06
If we ever meet up with an alien civilization, I'm betting they won't have Tetris, which will work to our advantage:
"We have come to share the secrets of fusion, interstellar tachyon drives, and matter transfer. What do you have to offer us?"
"Um, ultimate Frisbee, microwave popcorn, and, um, Tetris."
"Hmm. Tell us of this 'Tetris.'"
"Here, give it a try."
Six months later everyone on their planet will be staying up till four in the morning mumbling "All I need is a straight one. Just one." and we'll have infested the cosmos like fire ants.
And Happy Birthday Tetris!!