Pirate Rule Cameo
If you've got an eBook subscription over at Baen, then you may have already read Manxome Foe by John Ringo and Travis S. Taylor. If not, then you'll have to subscribe, or wait until it comes out in hardback in February of '08.
Either way, the "enemy of my enemy" rule gets mentioned in Chapter 13. Apparently I will finally get around to publishing Seven Habits of Highly Effective Pirates (and all the concomitant rules), because Lt. Fey is familiar with the book.