Would it be practical to make remote calls to the listen function? Usage: if I want to have a webpage read speech automatically to the user after a javascript event, without showing the google page. I expect the first step would be loading the page in a hidden iframe.
That actually is fairly similar to a webapp I built in 30 minutes a few months ago. I had the idea to build a webform that lets you type in some text, and the computer reads it back.
If you are using OS X, you should be able to use the `say` command to create a recording of a voice speaking a sentence. You could likely take that, pipe it into a file and serve it up in an <audio> tag and play it from javascript that way.
I might try hacking my project to do exactly that. However, I think a sane solution for you would be to make use of system accessibility options or screen readers. The downside there is that you can't call into those from a user's browser.