I thought it would be nice to shutdown with a menu command.
The program xmessage will allow you to setup multiple buttons, each with a different number. That number will be the return code for the program. Bash (bless its little heart) will allow you to query the return code in the variable "$!". They seem like a natural fit!
I did a little visudo so that my group could call shutdown without entering a password.
%admin ALL=NOPASSWD: /sbin/shutdown
Here's the contents of my shutdown script:
xmessage -buttons "Yeah boy!":0,"Quit rushin' me...":1 "Shut this bitch down?"
if [ $? == 0 ]; then
sudo shutdown -h now