Quoting Michael Burns (sextus at visi.com):
> I'd avoid putting advocacy in X-headers; it's not what they were allowed
> for, and putting 4 or 5 of them in every email dilutes your message and
> can make you look like a crank. If you are a crank, you can grind your ax 
> in your (on-topic) message or your .sig.

I believe the X-Headers are for whatever you want them to be. Yes, I have 5
X-Headers for reasons NOT to use Microsoft products or the extremes MS wil go to
to push their products.

And you are right, most MUAs don't even display them. My MUA, mutt, doesn't even
display them ala:

# Weed ALL mail headers, then put back the ones we want to see
ignore *
unignore from date subject to cc
unignore organization organisation x-mailer: x-newsreader: x-mailing-list:
unignore posted-to:

In my .muttrc, BUT many mailing lists I post to actually index the X-Headers, so
It's a good way for google to pick them up. :-)

Call them my subversive advertisments.
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