gtg

from The Free On-line Dictionary of Computing (8 July 2008)
gtg

   <chat> Got to go.  The user is about to stop chatting.

   (1999-06-07)
    
from V.E.R.A. -- Virtual Entity of Relevant Acronyms (June 2006)
GTG
       Good To Go (slang, Cygwin)
       
    

grant@antiflux.org