Zim Wiki - Zim is a graphical text editor used to maintain a collection of wiki pages. Each page can contain links to other pages, simple formatting and images.
TiddlyWiki - a non-linear personal web notebook
ConnectedText - ConnectedText is a powerful but simple information management system.
Torchpad - Wiki farm with markdown based wikis.
Book on a Stick - Write a book in one self-contained file that runs entirely in your browser and can be kept on...
wikidPad - wikidPad is an application for storing thoughts, ideas, todo lists, contacts, or anything else that user can think of to write down.