N900 as Bluetooth HID Device

I know it is possible to connect Bluetooth Keyboards to the N900. But what about the other way arround?

I would say it is possible. But I haven't found a way so far.

The Idea is to use the simply great N900 keyboard in moments you have no other keyboard or a regular is simply to big. At example as a Bluetooth Keyboard for your Playstation 3 or to have a Keyboard while using your new tablet PC (iTab) on the go or you have a Nokia N8 as your workphone and wan't to write a email the fast way.

It should be a simple app. As soon as you start it, it activates the Bluetooth stack and makes the N900 visible as HID Device. Then you can scan from the other Device (at example the WeTab) for new Bluetooth Devices and connect to it. When you type now at the N900 keyboard every keypress is sent over Bluetooth to the other device as long as this application is in the foreground. I guess there are some more use case.

Please forgive me if something like this already exists. If so, please help me to find a way to the solution.