[[:{{{1}}}:{{{2}}}|{{{2}}}]]
A namespace-linking simplifier. Put in {{S|X|Y}} for a shortcut of [[X:Y|Y]].
For example, {{S|Special|RecentChanges}} results in RecentChanges.
Since the syntax used here is fundamentally similar to the interwiki syntax, you can use this to link to an interwiki page as well; {{IW}} is an alternative for such linking that is capable of proper linking to pages with (parentheses) on the end.