"Colombia!" is a reference to a certain Japanese meme originating from a game show right? Can somebody explain it for me?
From what I understand, Panel Quiz Attack 25 (A name of Quiz show in Japan) has the question: “What is the South American country of sharing boundaries over land with Panama in Central America?” The answer is Colombia and the guy who answered it made a raised hands pose and smug expression. Because of the rules of the quiz game, he won expensive prize(s) by answering that.
However, before that, he got many 'easy' questions wrong. Irritated by his smug expression and 'lucky' win, 2ch users searched for his information in the web and found a confession from him about cheating in the qualifying test for the show.
Anyway, things happened after that information was spread. End result is that his reputation was damaged (He claimed that it was just a joke, but most people did not believe him).
I believe that the pose, the smug expression in the original picture, and the ensuing chaos is what made it quite (in)famous.