About

MER IL ET FOU, along with ENKULER DE RIRE and Si j'été pas là, vous seriez vous, are pieces of slang and image macros based on the casual misspelling of a 13 years old boy. They became famous and corny catchphrases used to express a wide variety of responses on the French web.

Origin

On September 27th 2009, on a forum hosted by Gamekult, a French website about video games, a user named Noyart (later revealed to be a 13-year-old boy named Gabriel) created a topic^[1] because he was in the middle of a dilemma in buying a game console and he wanted to know the pros and cons of a PSP (shown below).
While his message isn't that bad written, a peculiar sentence stood out: MER IL ET FOU

That sentence is written in all caps and initially emphasized that he anticipated being pointed out as crazy for planning to buy a PSP, supposedly because that game console, according to the video game media at the time, had some selling difficulties throughout the world.

MER IL ET FOU's in-joke is hard to translate. The sentence means But he's crazy! or He's crazy lol!, only with misgrammar commonly found in Lolcats. Mer, in this particular case, could either be a mistyping of the word mais, French for but, or a mistyping of a famous French acronym: MDR, from Mort De Rire (Dead from laughter in English) which is the French equivalent of LOL. It should be noted that et, French for and is also a miswriting of est, the French third-person singular conjugation of the verb be.

Instant celebrity

On the same day of the post, all the replies that followed featured the sentence, some of them already coupled with pictures and memes, without dealing with Noyart's initial request.

Noyart came back a first time, saying that he would finally go buy a PSP at the nearest shop^[2]. Overwhelmed by the constant stream of replies on his strange catchphrase, he came back a second time to give an ambiguous comment: ENKULER DE RIRE^[3].
Once again, this simple catchphrase, roughly meaning fucked by laughter, certainly a stronger version of the aformentioned acronym, caught on among members of the forum for its miswriting (enkuler is written enculer in french), misgrammar (the infinitive form enkuler was meant to be written as the past participle enkulé) and overall weird but funny phrasing.
Fearless, Noyart continued to play along with the posters and gave another strange comment, si j’été pas là, vous seriez vous^[4], which was again filled with misgrammar, mistyping and the usual weird phrasing. The sentence supposedly means If I were not here, where would you be in French.
The thread has extended to an impressive 73 pages of comments and replies as of December 2014.

Spread

The popularity of these three catchphrases exploded beyond Gamekult's website and they got featured in several blogs and articles dealing with the phenomenon, such as Paper Blog^[5], Oreille Malade^[6], Tuxboard^[7] and Nomnomnom^[8].
This was coupled with several Facebook fan pages for each buzzword, one of the most famous for MER IL ET FOU^[9], reaching more than 9 400 likes as of December 2014, as well as single-serving websites namely for ENKULER DE RIRE and MER IL ET FOU (both defunct as of December 2014).

Insight

Media recognition: Halo Reach

Halo: Reach is a first-person shooter video game published by Microsoft Game Studios for the Xbox 360 and released on September 14th 2010. The game contains many Easter Eggs, one of them being called the Doctor Halsey's lab or Tribute Room^[10].
In the French version of the game, the meme has been reused to appear on one of the computers' screens (shown below, at around 6:33 in the video):

The full transcript says:

SUBJECT: MER IL ET FOU
Curious. I don't recall opening this file. Perhaps I have a security breach?

It must be noted that the original transcript reads as SUBJECT: I LIKE PIE in the US version.

External References