A little something for my long-suffering OSX readers: a simple script to change your login background. Note that images must be in PNG format.
Copypaste the code above, save it as /usr/local/bin/set_login_background.sh, and execute like this (the first line is necessary only on first usage):
sudo chmod a+x /usr/local/bin/set_login_background.sh sudo set_login_background.sh /path/to/my-new-image.PNG
