Many contributors to projects of the Wikimedia Foundation (http://wikimediafoundation.org/ - most famous perhaps for Wikipedia, but they do all sorts of other things, too) have accounts on several of their projects (e.g. the English, French and Swahili Wikipedia and the French Wikisource), and from this week on, these can now be unified such that only a single login is required for all the projects one wishes to contribute. To do that, go to [[Special:MergeAccount]] on a project for which you are already registered. Help is available in quite a few languages via http://meta.wikimedia.org/w/index.php?title=Help:Unified_login .