Kchmviewer - Kchmviewer is a free, open-source CHM (MS HTML help) and EPUB viewer for Unix, Mac and Windows...

ManualsLib - Just enter the keywords in the search field and find what you are looking for!

WinCHM - Creating CHM file, Make CHM file, Web Help. WinCHM Pro - Help authoring software (CHM, WebHelp, DOC, PDF) . With this powerful tool you can not only create chm file from scratch, but also convert a set of existing HTML files to a chm file.

Dozuki - Dozuki is a web-based tool for creating and distributing step-by-step documentation.

CHM Editor - Best solution to edit CHM files

Manuzoid - Repository that includes user manuals for various products