Baneposting is a meme oringating from the /tv/ board on 4chan, bane posting has gained a cult following enough to warrent it's own board /bane/ on 8chan.
In early December 2011, a video clip of the prologue sequence from the then-upcoming 2012 superhero film The Dark Knight Rises was leaked online. The prologue features a CIA agent (played by Aidan Gillen) threatening three men with sacks over their heads aboard a moving airplane, explaining the first one to give up information would not be thrown out of the plane. The first two men are silent, but the third begins to talk with a muffled sounding voice. When the sack is pulled off, the man is revealed as Bane (played by Tom Hardy). He then reveals he plans to crash the plane with no survivors, which he does with the help of his associates, before escaping himself.
On December 11th, 2011, an audio file of the leaked scene was posted to 4chan’s /tv/ (Television & Film) board, featuring the following dialogue between Bane and the CIA agent (shown below). Soon, commenters in the thread began scrutinizing the last two lines in the dialogue, as some misinterpreted Bane’s interspersed quote “[it would be extremely painful] …for you” as a double-entendre with suggestive connotations, i.e., “[I’m a big guy] …for you.”
Baneposting is a popular meme on /s4s/, many users there commonly repeat the line "for you".
/bane/ is an 8chan board specifcally for baneposting.
Association With Germanwings Flight 9525
On March 24, 2015, Germanwings Flight 9525 crashed in the French Alps after French air traffic controllers lost contact with the plane less than an hour after takeoff. In the days following the crash, users on 8chan's /bane/ board began to note several similarities between the crash and the opening scene of The Dark Knight Rises (shown below).