You can create an ebook (epub), using the epub plugin. In Firefox you can install the
EPUBReader and read your manuals directly in the browser. Or you can use
Calibre, a first-class open-source epub reader with many options for file conversion, including converting ebooks to pdf. For a sample of what the epub plugin can do, see
the fckgLite ebook manual. FckgLite is now deprecated in favor of ckgedit, but the manual is still a good example of the epub plugin's capabilities.