demo mode

from Jargon File (4.4.4, 14 Aug 2003)

demo mode
 n.

   1. [Sun] The state of being {heads down} in order to finish code in
   time for a {demo}, usually due yesterday.

   2. A mode in which video games sit by themselves running through a
   portion of the game, also known as attract mode. Some serious {app}s
   have a demo mode they use as a screen saver, or may go through a demo
   mode on startup (for example, the Microsoft Windows opening screen --
   which lets you impress your neighbors without actually having to put
   up with {Microsloth Windows}).

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

demo mode

   ({Sun}) 1. The state of being {heads down} in order to finish
   code in time for a {demo}, usually due yesterday.

   2. <games> (Or "attract mode") A mode in which video games sit
   by themselves running through a portion of the game.  Some
   serious {apps} have a demo mode they use as a screen saver, or
   may go through a demo mode on startup (for example, the
   {Microsoft Windows} opening screen - which lets you impress
   your neighbors without actually having to put up with
   {Microsloth Windows}).

   [{Jargon File}]

   (1995-02-22)