Working on my own similar plugin, but its just as complicated almost :)
(Called ToothControl, just to have a name on it :)
Meedio -> ToothControlMee Plugin (Meedio Plugin) ->ToothControl Server -> Client (PDA, Sony Ericsson mobile phone etc.)
Prototype:
It doesnt really look nice atm, and limited options, but currently I can do mostly anything I want regarding adding,deleting from playlist, browsing through my music (the Meedio database), forward/rewind, change volume, play/stop/pause. Nice to see a list of 1000 artists show up on the PDA. And using the .NET Compact Framework the client program can be easily run on standard windows os.
Of course, Netremote can mostly do thing better, but nothing is as funny to be able to do it yourself.