Cosmos - C# Open Source Managed Operating System
Cosmos is an operating system project implemented completely in CIL compliant languages. The team is committed to using C#, however any .NET language is usable.This is the first public OS that is 100% written in C#. Cosmos is an independent open source product, licensed under BSD. Cosmos comes with a compiler (IL2CPU) that compiles the resulting intermediate language (IL) to X86 code. The compiler includes a cross-platform-support layer, and the Cosmos team says it plans to add support for other processors and platforms, including x64. Developers can use any .Net language to write to Cosmos.
So like to create your own website here is the link - http://www.gocosmos.org/