OK, couldn't find that list, so I've done a quick search of the net to pick out the most common ones.
<G> - Grin
AFAIK - As Far As I Know
ATB - All The Best
BBL - Be Back Later (Much later)
BBS - Be Back Soon (In a while)
BRB - Be Right Back (Just a minute or two)
BTDT - Been There, Done That
BTW - By The Way
F2F - Face to Face
FAQ - Frequently Asked Question(s)
FFS - For God's Sake
FOC - Free Of Charge
FWIW - For What It's Worth
FYI - For Your Information
HTH - Hope That Helps (Also "Happy To Help")
IIRC - If I Recall Correctly (Or "If I Remember Correctly")
IMHO - In My Humble Opinion (Or "In My Honest Opinion")
IMO - In My Opinion
LMAO - Laugh My Buns Off
LOL - Laugh Out Loud
NIMBY - Not In My Back Yard (My favourite!)
NRN - No Reply Necessary
OIC - Oh, I See
OMG - Oh My God!
OTOH - On The Other Hand
OTT - Over The Top
PMSL - Wet My Self Laughing
ROFL - Roll On Floor Laughing
ROFLMAO - Roll on Floor Laughing My Buns Off
RTFAQ - Read The FAQ
RTFM - Read The Bleedin' Manual
TTFN - Ta Ta For Now (Bye)
TVM - Thanks Very Much!
WTF - What The Heck?
WYSIWYG - What You See Is What You Get