Bug the NSA for a change:

Things to include in news/email...

[primary markings]

TOP SECRET

(TS)
[markings shown in parentheses are accepted abbreviations. For example,
you could just put (TS) on a document, instead of TOP SECRET]

SECRET

(S)

CONFIDENTIAL

(C)


[additional markings]

SENSITIVE COMPARTMENTED INFORMATION
[very secret intelligence information]

(SCI)

DISSEMINATION AND EXTRACTION OF INFORMATION CONTROLLED BY ORIGINATOR
[this marking, also written as ORCON, is used on information that
clearly identifies a US intelligence source or method]

(ORCON)

WARNING NOTICE - INTELLIGENCE SOURCES OR METHODS INVOLVED
[this marking is used on information that could identify an intelligence
source or method]

(WNINTEL)

SINGLE INTEGRATED OPERATIONAL PLAN - EXTREMELY SENSITIVE INFORMATION
[US nuclear war fighting plans]

(SIOP-ESI)

CRITICAL NUCLEAR WEAPON DESIGN INFORMATION

(CNWDI)

RESTRICTED DATA - This material contains RESTRICTED DATA as defined in the
Atomic Energy Act of 1954. Unauthorized disclosure subject to administrative
and criminal sanctions.
[used for nuclear secrets that are below CNWDI]

FORMERLY RESTRICTED DATA - Unauthorized disclosure subject to administrative
and criminal sanctions. Handle as RESTRICTED DATA in foreign dissemination.
Section 144b, AEC 1954.
[this label applies to nuclear secrets that have been transferred to a
military agency from the Department of Energy or it's predecessor, the
Atomic Energy Commission]

LIMITED DISSEMINATION
[used on information in Special Access Programs]

(LIMDIS)

FOREIGN GOVERNMENT INFORMATION
[classified material that originated with a US ally]

(FGI)

COSMIC TOP SECRET
[NATO (North Atlantic Treaty Organization) document that is 
classified TOP SECRET]

NATO SECRET

NATO CONFIDENTIAL

NATO RESTRICTED

ATOMAL
[NATO nuclear secrets]

NOT RELEASABLE TO CONTRACTORS/CONSULTANTS
[this might be used if the powers-that-be are discussing cancelling a
contract with an aerospace company...]

(NOCONTRACT)

CAUTION - PROPRIETARY INFORMATION INVOLVED
[this marking is used on documents that would prove harmful to a company.
For example, it could be marked on TRW documents that weren't supposed to
go to Martin Marietta Co.]

(PROPIN)

REPRODUCTION REQUIRES APPROVAL OF ORIGINATOR OR HIGHER GOVERNMENT AUTHORITY.

CLASSIFIED BY MULTIPLE SOURCES

NOT RELEASABLE TO FOREIGN NATIONALS
[under no circumstances can this data be released, not even to a US ally]

(NOFORN)
[this is the dreaded NOFORN marking that Cliff Stoll jokingly said meant
'No Fornication' in his book "The Cuckoo's Egg"...]