I would be interested to see if you could get something like this running using the Google NACL project (http://code.google.com/p/nativeclient/). Wouldn't that give you then benefit of having native code running on any machine that went to the page and had the plugin installed? You could have the user install a plugin when they went to the page and then reload the page. Just popped into my head, probably too late to implement anything now, but might be fun to give it a go.