Yet another form of rofl, loller, lawl, lol, that was made up by a person with the internet alias "JaJa". He makes über leet skeet words.
Variations of this word are lollerskeetz, roflskeetz, and roflskeet, which all mean basically the same, just a different way of laughing.
Jimbo: z0mg lazerz pew pew pew lazers i t0taly pwn'j you.
Smurf 1: Wtf mate, lollerskeetz
Smurf 2: ROFLSKEETZ he doens't know wat dat means, he's a ch00b.
Smurfer: wtf mate
JaJa: fucking noob