afk
As mentioned 27 times above afk refers to "away from keyboard". But seeing I first encountered this term in the german version of an online game designed by a company interested in weather turbulences, I took it to be a shortening of "auf klo" meaning "in sitting position, currently getting rid of the pizza I had for lunch". In 49% of all cases, this is an accurate rendering of the term when used in online communication situations. This word is not only used in written language but also in spoken. Anyway, in German the term has undegone significant extensions, resulting in:

with suffix
- afklo, also afkaken (as explained above)
- afkleenex (getting a tissue, winter phenomenon)
- afkaffee ( 49%, equal score to afklo, possible connection still to be researched.)

with prefix
- brain-afk ( used in in-game situations, work out meaning for yourselves. Being in a different category, this meaning is not included in the statistics above but would score significantly higher than either of the other two major forms.)
How could possibly not see this huge patch of nasty, green substance/ lethal dark purple verging on black substance/ flaming inferno on the ground, you brain-afk moron. (inadequate German translation and more polite than usual)

- bin mal afk
- re
- wb
- thx