Mesen 0.4.0 Beta

System Requirements

Windows Vista, 7, 8, 8.1 and 10 are supported
DirectX 11
.NET Framework 4.5+

Mesen is a NES/Famicom emulator and NSF player. It is still a work in progress - some features are currently incomplete or may change in future versions.
Features

High Accuracy - A lot of effort has gone into making Mesen as accurate as possible
NES and Famicom (including Famicom Disk System) support. Also supports: NSF, NSFe, VS System
Support for over 175 mappers
Supports: Save States, Movie/Audio Recording, Screenshots, Cheat Codes
Net Play - Play online with friends
Built-in Debugger
Automatic updates - Mesen is able to check for updates and automatically install new versions of itself.
Stand-alone - Put the Mesen application into any folder and run it from there
Other Features: 7z/zip archive support, numerous video filters (xBRZ, Scale2x, NTSC, etc.), sound recorder, sound effects, etc.

Technical Details

Core built in C++ with a C# user interface.
Multi-threaded - Emulation, Video Filters, Rendering, Net Play and UI all run in their own threads.
Runs in 32-bits or 64-bits mode depending on the operating system, with the same executable file

The name "Mesen" is both a Japanese word (目線 - meaning "point of view" or "a person's gaze") and a terrible pun on the term "NES Emulator": "NES Emulator" →　"NES Em" → "Mesen" (backwards)

http://www.mesen.ca/#MapperGrid