This is a NES emulator written entirely in vb.net. The emulator uses Direct3D to Render Video, DirectSound to emulate NES APU, and DirectIpunt to read Input from controllers/keyboard. It's still in early stages of development, but already runs many games.
You will need Visual Studio 2012 or 2010 and Managed DirectX. Just download the code and compile with Visual Studio. Make sure you have Managed DirectX installed and working on your VS Installation.