I've been using this software on my iPhone for the last 10 days or so, and it is awesome:

http://code.google.com/p/telekinesis/

It lets you access files, stream music and video, plus you can control your desktop, a la VNC. It can also take snapshots from your Mac's iSight camera and it can be used as a remote control for iTunes.. Right now it is Mac only, but they have been putting out updates for it almost daily, adding new features and bug fixes.

I tried accessing the network address from my N800, but no dice...something in there makes it Safari only. It would really be neat if it worked on the N800, but the program linked at the top of this thread looks like it is very similar...