MPDroid app (for android, of course)
trying it out on the 2 android tabs I have; the nexus one and the nook color (with cyanogen 7.x installed).
this app talks to the web back-end of mpd (music playback daemon). this is a music server that runs on linux and can be controlled via multiple ways. there is also a pretty nice web interface called 'neompd' (I think its just php stuff).
from anywhere in the house, you can control the playlist, which also includes internet radio as playlist entries (that just never 'finish' and stay until you change them).
I might try to have the vol control slider (which talks to mpd's idea of volume control) actually talk to my own VoluMaster system. it would be an easy way to have access to both playlist and also my preamp's volume control, all over wireless GUI remotes.
that nook holder/stand is kind of neat, too; its a cover and also has ribs to hold the tablet at a few angles. its not a novel concept but its well enough done, here.
cyanogen 'mod' version 7 seems somewhat stable (v9 sucked badly; lots of crashes and lock-ups) and you simply download an image to an entire micro-sd card, boot from the card (the nook color boots from sd-card by default, if present) and then follow some instructions. whole process was 15 minutes or so and then you can either flash the o/s internally (I did) or just keep running from sd-card. NC (nook color) was a good deal for getting access to a very usable capacitive touch tablet.