"All your base are belong to us!" phrase, Engrish. 'Net-ism:see addendum. See also zigspeak, Engrish. [EDE]
Addendum: In 1991, Taito released a side-scrolling sci-fi spaceship combat game for the Sega Genesis called Zero Wing (the arcade version came out in 1989). Besides being sucky overall, the English-language version of Zero Wing contained dialogue from the Japanese version, the translation of which was unusually bad, even for the video game genre. Here's the script from the opening animation:
Titles: In A.D. 2101, war was beginning.
Captain: What happen?
Mechanic: Somebody set us up the bomb.
Operator: We get signal!
Captain: What!
Operator: Main screen turn on!
Captain: It's you!!
Cats: How are you gentlemen!! All your base are belong to us. You are on the way to destruction.
Captain: What you say!!
Cats: You have no chance to survive make your time. Ha ha ha ha....
Operator: Captain!!
Captain: Take off every 'ZIG'!! You know what you doing. Move 'ZIG." For great justice.
Any way, a couple of years ago this text started circulating around video gaming sites on the Internet as an in-joke. Now it has blossomed into the "Mahir" of 2001. Gamers will use a variety of quotes in a variety of contexts, particularly variations of "all your base are belong to us," "somebody set us up the bomb," and "you have no chance to survive make your time." [EDE]
Addendum #2:Thankfully, this joke has long since bit the dust and become a symbol of annoyance, but occasionally will crop up every now and then.