Show My IP Addresses (External and Local)

How to get hostname or MAC address

Hi,
We are developing an HTML5 and JavaScript app where we need to uniquely identify the computer (by hostname or MAC address, or else) that is running the app. Do you think we can do that using a Web extension. And such a Web extension already exists? Or, otherwise, can you develop it? Or tell us how it can be done, it it's possible.
Best regards
Paulo Nunes