G15 Authenticator is a fully functional Battle.net Mobile Authenticator that displays your current Authentication Code in real time on your Logitech G15 keyboard. This allows you to keep your Battle.net account secure whilst not depending on an external accessory or device to do it for you.
Coming Soon! No, it is not ready for common use.
Also, if you manage to figure out how to operate it, make sure to back up your secret key somewhere that isn't your local computer but secure. If you don't keep it, you won't be able to generate codes to remove the authenticator in the future. If you end up losing the secret key, you will have to contact Blizzard support to have the authenticator removed and because this is third party software they probably won't be able to provide support for you.
It is, however, not against any policies for using your account to use third party authenticators.
You can read more about the Blizzard Mobile Authenticator at the Blizzard Support website.
Obviously, you need Eclipse IDE and a Java Runtime Environment. After exporting the project to a Runnable Jar, run this:
start javaw -jar *jarname*.jar secret-key time-difference
Right now the only way to generate the secret key and time difference arguments is to use the authenticator.jar in a similar manner, passing the argument GENERATE to it.
USE AT YOUR OWN RISK
If your account gets compromised or you are banned because you used this tool, it is not my fault. The source code is open to the public for a reason. Please only download the tool at: