Just a quick blurb while on a 2-minute work break.
I love ( LOVE!!! ) TiddlyWiki for building a context-sensitive help system for users of the software I’m maintaining/enhancing.
For any class of push button I drop on any window, I associate a help “title” for it (i.e. the name of a tiddler), and when the user clicks the button, up comes the help system in the web browser, displaying that tiddler.
This one TW provides help for five different applications, and the TW adjusts itself for whatever context (i.e. the app name), such that it makes available only the help documentation related to that context.
Totally rocks something silly/fierce.