Laugh spawned in the "Community" section of the original AOL series. It is a sarcastic way of
shrugging off a ill attempt at a flame, and/or
libel. Something to the extent of "Whatever".
It is mostly used by the lesser l33t of the internet community to make up for the fact they are what they are. (
Side note) Most counter-strike players use it.
Bill: DUDE
OMFGWTFBBQ YOUR A
IDIOIT
Bill: YOU NEED TO GO KILL YOURSELF WTF!
Bill: IF YOU DIDNT USE AIMBOT, ID
WTFPWN
Bob: laff.