The Nokia 770 is a handheld "Internet Tablet" -- a non-phone device that includes Bluetooth and Wi-Fi. See http://www.nokia.com/770 for details.
Recently, Nokia released a "Media Streamer" for the 770. It's an application that will stream available music from UPnP servers to the device for listening. The cool part it that the application will also control UPnP devices -- including the SoundBridge. It only works with nominal control functions -- only UPnP available functions, not the cool RCP-related functions -- but it's cool to have a handheld controller for the SoundBridge.
I have included a screenshot after the sig.