ttfn

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

   <chat> ta-ta for now - goodbye for now.  Used in the UK, USA
   and probably elsewhere.

   (1998-07-02)
from V.E.R.A. -- Virtual Entity of Relevant Acronyms (June 2006)
TTFN
       Ta-Ta For Now (slang, Usenet, IRC)
antiflux / dictionary / ttfn
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