Can't the current OVI suite do this? (I still use the old Nokia PC Suite, since it does everything I need.) Not sure it's available for Linux though.

It looks like this one uses a custom app on both sides to do this. No reason you couldn't write a pair of apps to do this on the N900. I just doubt there's much of a need for it really. Especially since the N900 has a full keyboard, where most Android phones don't.