Ivan Fyodorovich's comment about folklore was mentioned in today's question: "What if I made a lava lamp out of real lava?".
Randall Monroe, of xkcd fame, time travels four and a half years into the past to sign up for a MetaFilter account just so he can answer a recent question in Ask.
A little under three years ago a Mefite named kcds made a bold proposal for a product that now (according to multiple reddit posts) has been incorporated into gmail. Time to get your cut sir.
Today's XKCD strip links to a nonexistent Wikipedia word "malamanteau." Apparently its only prior use was in a 2007 AskMe answer by ludwig_van. There's a bit of controversy on the Wikipedia talk page over a dismissal of MeFi as an "unused website."
There have been 205 comments on Metafilter as a whole mentioning the movie "Idiocracy", some subset thereof expressing or implying agreement with the premise of the movie (stupid people breed more so we as a population are getting stupider). There have been 800 comments linking to or about the online comic strip xkcd, some subset thereof expressing or implying an agreement with the opinions found in that comic strip. There is now an xkcd comic strip expressing the opinion that the premise of the movie "Idiocracy" is incorrect. In the law game, this is what is known as a split in the circuits, and requires a decision by the Supreme Court, hence this MeTa post.
Someone went and implemented xkcd's internet map - it generates pictures like this. Matt, would you be willing to dump a couple days worth of access_log IPs into this tool?