Items that need to be documented (or documented better) about FlexWiki:

The original content from this page (the portion following these comments) does not actually list undocumented features. The original author was mistaken, as Tommy Williams points out in his update. A purist might say that the Textile features referenced below should not be used interchangeably with the wiki formatting features. The textile notation corresponds to HTML tags, which are meant to provide semantic meaning, not formatting. Thus the Textile + sign means "inserted text", not "underline," even if the visual result is actually an underline. However, the purists lost that battle with HTML long ago, and it doesn't seem likely to win out in wiki either. The only objection I can see to using the Textile features in place of the traditional wiki formatting is that it is inconsistent with base wiki behavior. However, I personally prefer using *bold* to '''bold''' because it is easier. Also, I would like to see the meaning of _ and + switched to align with the visual result, but since these are defined by Textile I suspect that ain't gonna happen. -- MarkVatsaas

Subscript and Superscript

_subscript is accomplished by adding a ~ before and after a word. For example, ~subscript~.

^superscript is accomplished by adding a ^ before and after a word. For example, ^superscript^.

Highlighting is accomplished by adding an @ symbol between the word you wish to highlight and the substring which is identified at the top of a page. For example, if you add @flexWiki=http://blah.com/$$$ and this string inline: @@InterWiki("flexWiki", "RobCaron", "RobCaron")@@, the result is RobCaron.

To underline a word or phrase, enclose it in + symbols without spaces. For example, if you type +This is an underlined sentence+, the result is This is an underlined sentence.

The highlighting is supposed to indicate a link that goes to another wiki somewhere. That @flexWiki bit is an ExternalWikiReference (see FormattingRules and ExternalWikis).

The other things you point out are part of the Textile formatting (again see FormattingRules).

The + indicates inserted text (- surrounding a word or phrase indicates deleted text).

One other thing: to achieve superscripting (again you'll find this in the Textile part of the FormattingRules), surround your text with ^.

-- TommyWilliams