Maybe an onion router like tor (http://en.wikipedia.org/wiki/Tor_(anonymity_network)) would work for you? I'm currently putting together a version packaged for the N800, I'm setting it up to be a null-configuration package (just install it, and set up the network connection to use it. There's a little bit more work to set it up in the current desktop version, if I get it done the way I want it'll be simpler on the N800). I may have a version ready in a week or so.