This phrase can be attached to virtually any sentence, as a way to express potentially impending danger for the sake of being accurate.
Student 1: So when do you graduate?
Student 2: 2014...that is, if the world doesn't end in 2012...
Student 1: What gives you that strange idea?
Student 2: Its what the Mayans predicted, and they've been right about a lot of stuff.
by Space Wrangler May 2, 2011
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