Tcl/Java consists of two pieces of software. Jacl is an
implementation of a Tcl interpreter written entirely in
Java. Tcl Blend is a Tcl extension that provides access
to Java from inside Tcl. One can prototype Java code
using Tcl, and much more.
PyREXX is a interprocess messaging server for routing remote prodecure calls using xml-based messages (Jabber, XML-RPC, etc), which will allow programs to interact more easily.
C++/Java-like interpreter written in C++, using Flex and Bison. Small kernel, user extensions (shared libs) allow to add functions and classes to the system.