Came upon this searching for "security clearance"...
My favorite: Don't ask LTC Steele to sign my copy of Blackhawk Down.
HAHA!
Thanks for posting.
Edit: Here's a pretty good addendum by some AF guy -
http://michaelzwilliamson.com/rants/skippylist.php
53. I may not hand someone an extra grenade pin and ask, "Did you lose this?" as a practical joke.