Visit the JSNES page…
The emulator is port of the Java-based vNES project. It uses the HTML
canvas element for screen rendering (sorry Internet Explorer users) although sound is not supported yet.
There are 17 working games to try. Most will run in Firefox 3.5 or Safari 4, but neither browser offers a playable gaming experience. You’ll be lucky to achieve 10 frames per second on the highest-specification liquid-nitrogen-cooled ninja PC.
The real revelation, however, is Google Chrome — it runs the emulator at full speed (50-60 fps) on a modest PC. Google’s
canvas performance optimization appears to be out-pacing the competition by a considerable margin. Both Mozilla and WebKit have raised bugs to investigate why there is such a noticeable speed difference.
See also: SitePoint’s Exclusive Interview With Ben Firshman, Creator of JSNES