Reinvigorating the Air Force Nuclear Enterprise by the Air Force Nuclear Task Force (24 October 2008) reveals the names of several more NSPDs relating to nuclear weapons:
National Security Presidential Directive-3, Defense Strategy, Force Structure, and Procurement, 15 February 2001 (S)
National Security Presidential Directive-4, Transforming Deterrence, 15 February 2001 (S)
National Security Presidential Directive-10, U.S. Strategic Nuclear Force, 21 December 2001 (S)
National Security Presidential Directive-28, United States Nuclear Weapons Command and Control, Safety, and Security, 20 June 2003 (S)
National Security Presidential Directive-35, Nuclear Weapons Deployment Authorization, 6 May 2004 (S//FRD)
We already know about NSPD-10, -28 and -35.
The version in Google Cache has details that the PDF version does not, such as the full titles of NSPD-3 and -4.
Presumably, some techno-illiterate thought he was doing national security a favor. Will you have trouble sleeping at night because Osama bin Laden now knows the title of NSPD-3 is Defense Strategy, Force Structure, and Procurement?
It is shame that the documents are classified, because if you were suffering from insomnia, my guess is that reading either would do the trick.