There's a gadget for Vista that allows WinMo phones to control WMP and Media Center over a BT connection. It works pretty well from what I've experienced.
Here's the SideShow client for WM6 mobile:
http://www.microsoft.com/downloads/d...displaylang=en
Then go to the gallery and download the Media Center gadget.
http://gallery.live.com/results.aspx?c=60&bt=8&pl=7