The Apad text editor is a light-weight developers editor. It provides syntax highlighting for most source files, it can open most image formats, and it is able to display web files. It requires little to no configuration before you start using it.
jThemeManager is a library that allows dynamic loading
of java LookAndFeel "themes" from Jar and Zip files.
It is not a general dynamic classloader but does a good
job when loading and changing the LookAndFeel.
CAXO (Component for Accessing XML based Objects) is mapping any xml based object to a multiline and editable tree structure. CAXO is a JComponent, and direct implementable in any swing container. In default configuration, CAXO is an xml browser or editor
Date Selector is a Palm-Pilot like Date Selection utility that can be used in Java Swing applications. It also comes with a DateEditor class that allows it to be used as the Cell Editor for a date field in a JTable.