JK

Just Kidding
Found on http://www.encyclo.co.uk/local/21662

Jk

Linear A assumed unoriginal drawing of ancient glyph source http://kereti.de/linearA/AB05.gif, png-ified ...
Found on http://en.wikipedia.org/wiki/Jk

jk

just kidding
Found on http://www.noslang.com/dictionary/j/

JK

just kidding You better say it quick.
Found on http://www.lagkills.com/gaming-acronyms.htm

JK

Short for `just joking`, `just kidding`
Found on http://www.ruf.rice.edu/~kemmer/Words04/usage/slang_internet.html
No exact match found