I noticed a little bug with the FM tuner in the N800: when it's plugged into the charger and you turn the unit off without stopping FM radio play first, the tuner stays on and continues to play. You still hear the FM radio even though the N800 is apparently off. If you turn the N800 back on, the FM tuner applet shows the FM radio as stopped, and you have to toggle Play/Stop to get it back in sync again and actually turn it off. It only seems to happen when it's on the charger, so I guess the FM tuner circuit is in the part that stays on to provide the "Charging" display.

And BTW it would be nice if the FM tuner applet retained the current station setting when you toggle it on and off the desktop. It does retain the list of local stations as well as the preset desktop position, so at least it has some memory - just not the current station setting.