Snes9x is a portable, freeware Super Nintendo Entertainment System (SNES) emulator. It basically allows you to play most games designed for the SNES and Super Famicom Nintendo game systems on your PC or Workstation; which includes some real gems that were only ever released in Japan.
Snes9x is the result of well over three years worth of part-time hacking, coding, recoding, debugging, divorce, etc. (just kidding about the divorce bit). Snes9x is coded in C++, with three assembler CPU emulation cores on the i386 Linux and Windows ports.
Currently there are many ports of Snes9x available, please check the download page to see if a port exists for your system.