JSpice is an implementation of the OpenSpice programming language specification (see http://www.openspice.org/). OpenSpice is an attempt to make the features of a powerful modern programming language accessible to occasional programmers.
...It supports the lambda-calculus and object-oriented techniques. All statements are writeen in reversed polish notation. Java-classes, objects and methods are easily accessible with the dot-notation.
The only -complete- XUL/embedded scripting solution for Java. JFCML supports not only AWT and Swing; but any class accessible to Java's ClassLoader. Also, most major scripting languages, including JavaScript, BeanShell, Jython, Jacl (Tcl), JRuby, more.