XUP (Extensible User Interface Protocol) is a SOAP-based protocol for delivering events and incremental UI updates. This project builds a web application development framework on top of XUP, consisting of a client, a server toolkit, and a template viewer.
InterPython (stands Python InterOperability) is a .NET library that allows a python interpreter to be "embedded" in your .NET programs, and gives you (almost) transparent access to python libraries and services in .NET programs. Great for GUIs, etc.