When two fencers engage one another in a Facebook "poke" war, or otherwise fencing-like internet based activity. Usually followed by a thread of messages or wall posts over who got the touch.
*poke* Ha! You didn't even parry!
*poke* Wtf? No, screw you! I parry and riposte and hit you straight in the mask!
*poke* So, it's a Cyber Fencing bout you want, is it?
This can go on for a VERY long time