Precision Helper works natively with the Microsoft HTML Help projects format (HHP) and allows to publish resulting help to the CHM, WebHelp, ePUB (e-book), PDF and the single html document formats.
Precision Helper is designed for advanced developers and authors, but user-friendly environment enables creating help projects also by novice users.
Vote:
http://www.portablefreeware.com/index.php?id=1822
Note: they say
I'll try to find those .dll files. Still a great tool.Microsoft Html Help Workshop must be installed to properly compile resulting help.
In fact, only a few dll files from this product are needed, but Microsoft does not
recommend to install and register them outside of it's product.