Akronim

ASAP : As Soon As Possible
BTW : By The Way
FWIW : For What It's Worth
FYI : For Your Information, or For Your Interest
IMHO : In My Humble Opinion
OTF : On The Floor (laughing); writing is funny

ROTFL : Rolling On the Floor Laughing; writing is very funny
YMMV : Your Mileage May Vary; exact results are not guaranteed
OIC : Oh, I see...
OTOH : On The Other Hand
OTTH : On The Third Hand; writer has three alternatives, and hands
RSN : Real Soon Now
so : significan other: spouse or near-spouse
sp? : spelling?; writer is unsure of the word's correct spelling
TIA : Thanks In Advance