メーリングリスト
Wikipedia has a number of project mailing lists; the general project-wide list is Wikipedia-L. It's an essential resource for Wikipedia authors. Maybe you don't want to clutter up Wikipedia with questions or discussion. Or maybe, for whatever reason, you'd just like to chat with other Wikipedians without doing so via the wiki format. Great, then sign up for Wikipedia-L!
Since Wikipedia-L developed into an extremely high traffic list, a separate mailing list for the English Wikipedia was created. For discussion of issues concerning the english wikipedia only, please sign up for WikiEN-L and keep Wikipedia-L for general policy discussions!
There is also a general mailing list for interlanguage issue discussions and cooperation: Intlwiki-L. Use this list for things that specifically concern cross-language issues, or for discussing the setting up of a new language.
There are also language-specific mailing lists for Wikipedia in Danish, Dutch, Esperanto, French, Polish, and Portuguese.
And, there's a mailing list for technical discussions regarding development of the Wikipedia software: Wikitech-L.
Wikipedia also has a real-time chat channel. Visit Wikipedia IRC channel for more info.