History on the BBC website, includes items on World War II, the 1924 Everest expedition, and British history timelines. This is great fun, if rather unweildy. Check out the games section - great for kids as well as bored academics. This section of the BBC site contains information on their oral history project 'The Century Speaks', with audio clips. This is the 20th century section of the Avalon Project at the Yale Law School, including a large number of international relations texts, such as the Anglo-Russian entente of 1907, the Bretton Woods Agreements, the Balfour Declaration, British White Papers on Palestine and the NATO Treaty of 1949.
Data goes back quite a long way, and it contains a huge set of links as well.