Wikipedia
ESys.net is a hardware system design library for the .net/ Mono frameworks that is basically a port of the SystemC framework for C++. Entirely rewritten in C#, the framework allows "most of the concepts found in the SystemC environment [...] and all the operating system primitives planned in SystemC 3.0" to be used.
The target is to overcome several of SystemC's limitations that arise from the usage of C++ by porting the framework to a language that offers features that make subsequent tasks easier to accomplish. These features, such as reflection / introspection, the translation to an intermediate representation instead of machine code (the CIL) that still contains information about user-defined classes, platform independence and extensive thread management functionality, are supposed to allow for faster development and easier debugging of systems.
The framework's source code has been published under the LGPL license.