i really haven't changed mine drastically, 'cause i actually like the stock gnome look (i guess that's pretty vanilla of me..). i got rid of those pesky desktop icons.. changed the background image.. kept the nice blue clearlooks theme
i fired up gnome-screensaver. now i need to find the pacman screensaver somewhere
i think my next experiment will be mpd. probably with one of the console clients to begin with--the curses one (i think it is ncmpc) looks pretty nifty.