A simple, one line command to fix a broken gnome panel & restore it to the default settings. I came across it after I accidentally deleted my Gnome panel. Lately I have found it useful for situations where the panel just becomes corrupt (I am always switching monitors) or the panel just won't do what you want it to do (hidden sound, network, time applets etc). Tested on Ubuntu 10.04.3 LTS (Lucid Lynx).
Use at your own risk, no responsibility taken, this might break your machine, etcetera, etcetera.
gconftool-2 -shutdown && gconftool --recursive-unset /apps/panel && rm -rf ~/.gconf/apps/panel && pkill gnome-panel