I more-or-less randomly wondered about the origin of the phrase, “My hed iz pastede on yay!” and did a quick google search (the phrase + “origin”). This led me to the Google Meme Observatory, which I am hereby posting so that I can come back and look at it when I have time to, y’know, look at it.
As for the phrase, someone had tracked it down to a particular ex-LJ community, and found the original April 16 post in which someone coined the term regarding an apparently bad image manip featuring the faces of Merry and Pippin. One of the replies: “you do realize you’ve started a goddamn PLAGUE with that expression over at livejournal?” Prophetic words, indeed.