Mesen v0.4.2 is released. 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.

Mesen Features:
* High Accuracy - A lot of effort has gone into making Mesen as accurate as possible
* Stand-alone - Put the Mesen application into any folder and run it from there
* Supports: Save States, Movie/Audio Recording, Screenshots, Cheat Codes
* Supported Mapper List (130+): 0 to 13, 15 to 19, 21 to 27, 32 to 34, 37, 38, 44, 45, 47, 49, 52, 57, 58, 60 to 62, 64 to 80, 82, 85 to 89, 91 to 95, 97, 99, 101, 107, 112, 113, 115, 118, 119, 137 to 141, 143 to 157, 159, 163, 164, 176, 180, 184, 185, 189, 191 to 195, 200 to 203, 205 to 207, 210, 218, 225 to 228, 230 to 232, 240 to 243, 246
* NES and Famicom (including Famicom Disk System) support. Also supports: NSF, NSFe, VS System
* Net Play - Play online with friends
* Automatic updates - Mesen is able to check for updates and automatically install new versions of itself.
* Built-in Debugger
* Other Features: 7z/zip archive support, numerous　video filters (xBRZ, Scale2x, NTSC, etc.), sound recorder, sound effects, etc.

Mesen v0.4.2 Changelog:
This release is a beta - save states, movies, etc. created with this version may not be compatible with future versions of Mesen.

New Features
* UNIF: Added support for UNIF files.
* Cheats: Added a built-in cheat database containing cheats for over 750 games.
* Cheats: Cheat window has been reworked and added support for FCEUX (.CHT) and Nestopia (.XML) cheat file formats.
* Compatibility: Added support for 7 new mappers (105, 106, 117, 162, 186, 196, 219)
* Bug Fixes

* IPS: Fixed a number of issues with IPS files.
* Accuracy: Improved IRQ timing for RAMBO-1 chip (Mapper 64) - improves Skulls and Crossbones.
* Accuracy: Fixed issues with Gradius II, Crisis Force and Cosmo Police Galivan.
* NSF: Fixed sound tempo in Dendy mode.

Download: Mesen v0.4.2
Source:Here