1917.com: Russian Marxist site in English. Includes a work cataloguing current leftist parties in Russia.
Anglo-Catholic Socialism: Social gospel. The socialism of religion.
Computers and Socialism: Ideas on the topic from Andy Pollack.
Jubilee Group: A loose international network of socialist Christians, mostly within the Catholic tradition. Site includes articles, publications, events and contact information.
La Revolucion: A site of multimedia information and links.
Red Future: News about the Left. Information on Marx, Engels, Lenin, Trotsky, and Guevara.
Red Piranha: Repository of information about the history, leadership and current politics of left-wing parties and movements around the world.
The Co-operative Commonwealth/William King Server: Named after the leading advocate of the "Cooperative Commonwealth," this site explores that concept of socialism as well as others such as 'guild socialism.'
The Death of Socialism by Roger Kimball: Essay examining the decline of socialism.
The Socialism Organization: Essays and news archives from China's People's Daily, chatroom and links about socialism "with Chinese characteristics." Sponsored by the Wyith Corporation of Hong Kong.
Wikipedia: Socialism: Definition and discussion of the subject from the online encyclopedia, Wikipedia.