PDF Joiner - This online tool allows you to join several PDF documents into a single file, free of charge.
Kchmviewer - Kchmviewer is a free, open-source CHM (MS HTML help) and EPUB viewer for Unix, Mac and Windows...
DocuPUB - DocuPUB is an online file converter, file merger, file compressor, and file resizing tool.
Read CHM - Read CHM is ultimate CHM (Compiled HTML Help) file reader.
PDFChef Merge PDF - PDFChef Merge PDF is an online tool that allows you to merge multiple PDf files into one quickly and securely.
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.