autorun link from web page text to system text to speech

I want to install a button on my web page that grabs the text and throws it to the system built 'text to speech' I need it to work from all browsers and have a link that is for "mac osx" or "windows" The button would need to be installed on a wordpress site or added to a tradition html setting. The intellectual property and code will be retained by me. I would likely call on you in the future for further development, however I will need full disclosure on your method of execution before we start. If you are using other bits of code these would need to be free or custom so there will be no legal issues with use. Can you do this?