Bsnes is a Super Nintendo emulator that's been around since 2004 and is known for its efforts to reproduce Super Nintendo games in pixel perfect accuracy.
The emulator also gives special focus to ensuring that your gaming experience is as bug-free as possible. However, in order to reproduce the speed and playability of SNES games, the RAM load of Bsnes is quite high and you may experience some freezes if you're working on a slower system.
It doesn't help that Bsnes heavily utilises Direct3D, OpenGL, DirectSound and DirectInput to get such good results but the payoff is probably worth if you're running a faster machine. However, even if you do have decent hardware, you'll probably experience a few bugs and crashes as it is still very much a work in progress.
If you had a Snes or loved the old console, then Bsnes is surely one of the most accurate emulators out there.