Channel is a C++ template framework for distributed message passing and event dispatching. Its major components (message IDs, routing algorithms...) are highly configurable as template parameters. As a namespace shared by peer threads, channels support publish/subscribe scope control, message filtering, and translation.
Babel is an IDL-based language interoperability tool specific to engineering and scientific applications. It allows Fortran 77, Fortran 90, C, C++, Java, and Python to call each other in a single address space for maximum performance. Babel won a 2006 R&D 100 award from R&D Magazine.
MynahSA is a cross-platform toolkit for connecting C++ objects to data streams. Developers using MynahSA can quickly and easily create client/server applications or encrypted files containing serialized object data. The toolkit uses OpenSSL for encryption and secure network communications. MynahSA is tested on Linux, Microsoft Windows, Apple's Mac OS X, and Sun's Solaris.
SpoonRPC is a library providing a distributed message passing system in Python. It attempts to be as simple to use as possible with little boilerplate code. It provides safe, efficient object serialization (not using pickle) and message routing. RPC is not (currently) implemented, despite the name.