AFAIK: As far as I know
AFK: Away from keyboard
AKA: Also known as
ASAP: As soon as possible
ASL: Age, sex, location
B/C: Because
B/W: Between
B4: Before
BBIAB: Be back in a bit
BBL Be back later
BF: Boyfriend
BFF: Best friends forever
BFN: Bye for now
BOT: Back on topic
BRB: Be right back
BTW: By the way
CBF: Can't be fucked
CTN: Can't talk now
CYA: See ya
CYE: Check your e-mail
DIY: Do it yourself
FWIW: For what it's worth
FYI: For your information
GB: Goodbye
GF: Girlfriend
GG: Good game
GJ: Good job
GL: Good luck
GR8: Great
GTG: Got to go
HOAS: Hold on a second
HTH: Hope this helps
IAC: In any case
IC: I see
IDK: I don't know
IIRC: If I remember correctly
IMO: In my opinion
IRT: In regards to
J/K: Just kidding
K: OK
L8: Late
L8R: Later
LMAO: Laughing my ass off
LMK: Let me know
LOL: Laughing out loud
LQTM: Laughing quietly to myself
MMB: Message me back
MSG: Message
MYOB: Mind your own business
N/A: Not Available
NC: No comment
NE1: Anyone
NM: Not much
NP: No problem
NTN: No thanks needed
OMG: Oh my god
OT: Off topic
PLS: Please
PPL: People
PWN: Own
ROFL: Rolling on the floor laughing
STFU: Shut the fuck up
SUP: What's up
TBA:To be announced
TBC: To be continued
TBH: To be honest
TC: Take care
THX: Thanks
TIA: Thanks in advance
TISNF: That is so not fair
TMI: Too much information
TTYL: Talk to you later
TY: Thank you
U2: You too
UR: Your
W/: With
W/E: Whatever
W/O: Without
W8: Wait
WB: Write back
XOXO: Hugs and kisses
Y: Why
YW: You're welcome
Have any i don't have listed? Post them here