ROFF = Rolling On the Floor Farting, farting because the situation is so funny you can no longer control your bodily functions. ROFFing surpasses ROFLing.
A typo for ROFL, that is pretty funny when you say it, it gets stuck and you end up saying it all the time. Normally signifies that it is less funny that rofl, as heh is for stuff less funny than haha
<Rogultgot> Ich habe einen....pie
<Bacon> roff
<Bacon> ...I mean rofl
<Bacon> wait, no, roff is good
Welcome to Roff, Roff is basically the same as Rofl (Rolling on the floor laughing) but is used when something is more hilarious. Roff originated on the internet in gaming communities.