BUU's right - don't do that. Do you mind saying what influenced you to change the default value of $\ in the first place? Have you been doing it in order to save a bit of typing when sending data to STDOUT? In other words, do you have a coding style similar to:

   sub display {
      local $\ = "\n";
      print "This is the first line. Look ma, no newline";
      print "This is the second line.";
   }
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In a brief Chatterbox discussion on this point, Zaxo made the comment that Archive::Zip could avoid this type of problem by localizing $\ itself.