Standard wiki URI
In HTML and XML referring to articles in the GFDL text corpus standard wiki URI is stated as follows:
protocol://language.service_domain.top_level_domain/wiki/page_name/subpage#section
Only the "/wiki/" is constant. These are relatively easy to remember, e.g. one can easily rattle off URIs of the form http://en.wikipedia.org/wiki/troll where only troll must change to find some other article.
Supporting these radically simplifies wiki linking. Unfortunately neither MediaWiki nor GetWiki imposes them as a default. They really should.
See Wikinfo: standard_wiki_URI for more, and interwiki link standard for the equivalent issue for links within the GFDL text corpus.