HelpNDoc - What is HelpNDoc ? Easy to use yet powerful help authoring environment which can generate various documentation formats from a single source.
HelpSmith - HelpSmith is a help authoring tool to create CHM HTML help files, manuals, and PDF documents.
Dr.Explain - Dr.Explain software is a help file authoring tool.
StepShot - Make knowledge sharing more time-efficient!
HelpScribble - HelpScribble is a full-featured help authoring tool for easily creating professional Windows help files from start to finish.
Dokit - The solution for disseminating know-how: work instructions, procedures, knowledge base, documentation techniques, product support, wiki enterprise.