NanoProxy - Java to .NET Interoperability
This is a Java to .NET interoperability provider I wrote for my Computer Science Department Honors project. It works by exposing a set of Java classes to .NET via an unmanaged bridge. This could be potentially useful in the situation where interoperability is desired on a machine level, and the verboseness of TCP/IP or Web Service interoperability creates performance problems.
The project hasn't been updated since 2005, and while it was successfully working it was never polished off and is not ready for anything other than academic use. Nonetheless the subject material can be interesting if you are curious about platform interoperability or .NET and Java themselves.