How to change that boring 'Other Users' icon in your login-window to something funnier. The trick is done with the following shell command:
% cp UsersPref.tiff.new /System/Library/CoreServices/\
SecurityAgentPlugins/loginwindow.bundle/Contents/Resources/UsersPref.tiff
This assumes you have a tiff-file of 48x48 pixels called UsersPref.tiff.new in the working directory, of course.
Mac OS X Hints
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