"After conducting an exhaustive inventory of Russian nuclear weapons in the 1990s, former Secretary of Russia's Security Council, Gen. Alexander Lebed found that 84 "suitcase" nuclear bombs had vanished from the Russian arsenal." I know it's old news.. but was it ever figured out if they were actually missing or if it was a "paper work" mishap? Edit: Here's a good article about the whole thing: http://cns.miis.edu/pubs/week/020923.htm
That story has been bouncing around since the mid-90's. I tend to think that sloppy accounting during the end of the Soviet Union is more to blame than anything else - paper work mishap as you say.