gconf

I've edited my gconf for the first time ever today. I didn't really want to, but there was no other way to change the shutdown behaviour of Ubuntu Jaunty. Nowadays when choosing Shutdown a dialog box pops up saying that the PC will be shut down in 60 seconds. This can be suppressed by opening the gconf-editor and searching for shutdown (with both options 'search also in key names' and 'search also in key values' enabled). The key you want to edit is found in /apps/panel/applets/applet_fusa_auto_migrated/prefs/suppress_logout_restart_shutdown and by enabling the checkbox the confirmation dialog is suppressed. Voila!

Actually, in Ubuntu 9.04 Jaunty Jackalope it can also be changed, I found out later, by right-clicking on the 'new' log-out/IM status button and choosing preferences. There is a check box for 'Show confirm dialogs for logout, restart and shutdown'.
That makes it a bit easier, but now that I've discovered gconf-editor, I find it really handy for changing a lot of things :)