Netduino
Thinking what is Netduino ???
Netduino is an open source electronics platform using the .NET Micro Framework influenced by the Arduino hardware platform .
The .NET Micro Framework Provides the ease of of high-level coding along with the microcontrollers.
Netduino allows the Development using Visual Studio 2010 on the Micro Framework Platform.
You can find more Help from Getting Started with Netduino
You can download the SDK’s along with the Development Environment here .