Intel stressed that the extension is not aimed just at browser-based games. Web-based, compute-intensive photo-editing applications could be a target. In a demo of River Tail, Intel showed how River Trail improved the performance of particle physics simulator 15-fold, from 3 frames per second to 45fps.
Still, the River Trail page recommends that "River Trail is a prototype, and the extension is not yet meant for use on the public web. Please uninstall or disable the extension when surfing the web and use it only for web pages you trust."
Currently River Trail is available only for Firefox, downloadable at github.com. Intel would like to see the extension added to other browsers, too.