+User registration can be done using a web form, or ikiwiki can be
+configured to accept users authenticated with OpenID, or HTTP basic
+authentication, or other methods implemented via plugins.
+
+### Discussion pages
+
+Thanks to subpages, every page can easily and automatically have a
+/Discussion subpage. By default, these links are included in the
+[[templates]] for each page.
+
+### Edit controls
+
+Wiki admins can [[lock_pages|page_locking]] so that only other admins can
+edit them. Or a wiki can be set up to allow anyone to edit Discussion
+pages, but only registered users to edit other pages. These are just two
+possibilities, since page edit controls can be changed via plugins.
+
+### [[PageHistory]]
+
+Well, sorta. Rather than implementing YA history browser, it can link to
+[[ViewVC]] or the like to browse the history of a wiki page.
+
+### Full text search
+
+ikiwiki can use the [[HyperEstraier]] search engine to add powerful
+full text search capabilities to your wiki.
+
+### Commit mails
+
+ikiwiki can be configured to send you commit mails with diffs of changes
+to selected pages.
+
+### [[w3mmode]]
+
+Can be set up so that w3m can be used to browse a wiki and edit pages
+without using a web server.