TuxNES is an emulator for the 8-bit Nintendo Entertainment System that runs under Linux and FreeBSD on i386 machines. It supports a wide variety of graphic displays, sound modes, nifty features, and, of course, NES games.
Information regarding Project Releases and Project Resources. Note that the information here is a quote from Freecode.com page, and the downloads themselves may not be hosted on OSDN.
This release includes complete sound support,
complete MMC2 support, new MMC4 support, joystick
remapping, NetBSD and experimental OpenBSD
support, and ZIP file support.