PDFhelp is a replacement for the JavaHelp system based on the LGPL version of JPedal PDF library. It lets you to display PDF help content from the web from within your application, using only a few lines of code.
There are some tutorials (naturally in PDF format) on the downloads page.
HelpSetMaker - tool for creating structured online help and other help documents. Specially suited for the JavaHelp system. Creates JavaHelp HelpSets, HTML4 webpages and LaTeX source code. Written completely in Java, runs on any Java2-capable platform
HM2JHelp is a utility application designed to allow JavaHelp to be generated using the HTML help files created by the commercial application, Help & Manual by EC-Software GmbH
j2b provides an intuitive interface for users to be able to create a JavaBean, without knowing how to construct one. A publishable bean consists of a JavaHelp and icons, for which an integrated JavaHelp Wizard and icon editor were developed too.
...Add-ins for text, and for syntax highlighting source code are provided.
Aesop is a fledgling Eclipse wannabe looking for add-in developers.
Aesop makes use of JEditTextArea and JavaHelp.
This aims at moving C++ libraries into the Java culture with the help of Swig, XML, and XSLT: Java, JNI, JavaHelp, JavaBeans, RMI,JDBC, Servlets, JSP, EnterpriseBeans,
Jini, JMX, etc. is generated.
The JavahelpServlet is a Java Servlet that allows accessing JavaHelp documentation systems on the World WideWeb. It uses exactly the same input files as the original JavaHelp system and transforms it to HTML which imitates the original JavaHelp browser.