WebCL: OpenCL For The Browser
Phoronix: WebCL: OpenCL For The Browser
Nokia team give Image procesing as example
of WebCL use.
And WebCL can be 100x faster than JS!
And if GPU is idling then why not use it for some computing?
And WebApps may need some extra horse power. (stfu, those of you that forbid web apps to become complex stuff).