"Because a simple to use interface should also be simple to program."
Æjaks combines the server-side Ajax windowing system Echo2 with the powerful simplicity of the Tcl langauge. The result is a rich development environment in which to develop Ajax-based web applications, often with much less code to write. Æjaks runs on top of a Java Servlet engine, and can make use of any existing Java library.
http://aejaks.sourceforge.net