OT

from Jargon File (4.4.4, 14 Aug 2003)

OT
 //

   [Usenet: common] Abbreviation for "off-topic". This is used to respond
   to a question that is inappropriate for the newsgroup that the
   questioner posted to. Often used in an HTML-style modifier or with
   adverbs. See also {TAN}.

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

OpenTransport
OT

   <networking> (OT) A complete reimplementation of all levels of
   the {Macintosh} {networking} code including "Classic"
   {AppleTalk} and {MacTCP}.  It appeared in {MacOS} revision
   7.5.3 [or earlier?  Date?].

   (2000-08-13)

from V.E.R.A. -- Virtual Entity of Relevant Acronyms (June 2006)

OT
       Off Topic (slang, Usenet)

from V.E.R.A. -- Virtual Entity of Relevant Acronyms (June 2006)

OT
       Object Technology

from V.E.R.A. -- Virtual Entity of Relevant Acronyms (June 2006)

OT
       Open Transport (Apple)