I have gone through "Members of the British Parliament" and cross-checked their wikapedia articles for Cabinet positions adding to sub-cats as appropriate. In addition, I have the following posts whithout sub-cats:

Clement Attlee: Secretary of State for Dominion Affairs

William Aitken: Minister of Information, Minister of Supply

Francis Bacon: Attorney General, Lord Chancellor of England

George Douglas Campbell: Postmaster General, Secretary of State for India

Neville Chamberlain: Minister of Health

Winston Churchill: First Lord of the Admiralty, Minister of Munitions, Secretary of State for War, Secretary of State for Air

Robert Gascoyne-Cecil: Secretary of State for Dominion Affairs, Secretary of State for the Colonies

Harold Macmillan: Ministry of Housing and Local Government, Secretary of State for Air

Margaret Thatcher: Secretary of State for Education and Science

The Sec. of State for Dominion and for Colonies are junior cabinet positions subordinate to Foreign Sec. Likewise Sec. of State for India. The Sec. of State for Air is equivalent to US Sec. of the Navy but for the RAF. That is, it was a cabinet position (created in 1917) but was eliminated with the creation of Minister of Defense.

Also see: Category talk:Ministers of Defence (UK), Category talk:United States Secretaries of the Navy, and Category talk:British Foreign Secretaries for outstanding issues. ML4E 19:58, November 26, 2011 (UTC)