"For realz laugh"; To help distinguish when you *actually* laugh out loud while talking to someone over the internet. As opposed to "LOL," which is commonly used without laughing out loud.
In practice ROFL > FRL > LOL
Nathan: Are you at work?
Alex: I'm not even dressed yet
Alex: in fact, I'm just sitting here eating cereal and watching porn
Alex: and rolling in my money bin
Alex: drinking the blood of virgins
Nathan: *shakes head*
Alex: no, I'm at work
Nathan: I am FRL
frl - noun - a contraction of "for real".
Subject A: "Isn't soulseek the greatest thing on Earth?"
Subject B: "FRL"
"Flashing Red Light Syndrome"
When you think the light on your blackberry is flashing informing you of a missed call, text or bbm but in reality you are just imagining it.
Me "I swear I just got a text."
Steph "Nah you've just got FRLS"