This refers to the alleged scanning of all Usenet traffic by the
     National Security Agency (and possibly other intelligence
     organizations) for interesting keywords.  The "food" is believed to
     contain some of those keywords in the fond hope of overloading NSA's
     poor computers.  Other posters have taken up this practice, either
     as an ambiguous form of political statement, or as an attempt at
     humor.  The bottom line is that excessive signatures in any form are
     discouraged, the joke has worn stale amongst long-time net readers,
     and there are specific newsgroups for the discussion of politics.

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