v. roffle·d, roffle·s, roffl·ing, roffle·mao
1. To laugh so hysterically that one begins to roll on the floor.
2. To roll on the floor laughing hysterically, occasionally causing one's posterior to fall off.
2. "Goddammit, I just roffled my ass off!" exclaimed Jon.
ROFL = Roll On Floor Laughing.
Which is a term widely used in internet chatrooms and instant messaging software.
Roffle evolved due to people readling ROFL like a normal word rather than spelling out each letter as R. O. F. L.
Roffle is therefore the casual friendly way to say ROFL and can be used as a verb in its own right:
"Ess Tee Eff Yoo"