He said he wasn't sure if something very specific had been done or not. Depending on what exactly you wanted, it may or may not have been (though it's looking like the former) the same thing you were asking about.

I am pretty sure it's possible to just use a usb-to-ethernet adapted, and plug the other end into the N900. There's no easy way to do it, you'd need power kernel or mad developer to install the necessary usb module software on your N900, and you'd probably have to do some command-line stuff to make it happen. But it shouldn't be impossible.