catatonic

catatonic adj.  Describes a condition of suspended animation
   in which something is so {wedged} or {hung} that it makes no
   response.  If you are typing on a terminal and suddenly the
   computer doesn't even echo the letters back to the screen as you
   type, let alone do what you're asking it to do, then the computer
   is suffering from catatonia (possibly because it has crashed).
   "There I was in the middle of a winning game of {nethack} and
   it went catatonic on me!  Aaargh!" Compare {buzz}.