cat /bin/true

#     Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T
#       All Rights Reserved

#     THIS IS UNPUBLISHED PROPRIETARY SOURCE CODE OF AT&T
#     The copyright notice above does not evidence any
#     actual or intended publication of such source code.

#ident  "@(#)true.sh    1.6     93/01/11 SMI"   /* SVr4.0 1.4   */

I'm not sure what I like most. The fact that they're claiming strict copyright on a file that is all comments? The fact that they're up to version 1.6 of all-comments, after five years of development? Or the fact that the GNU version had to be rewritten (due to the above copyright), and thus actually offers three times as much functionality?