Am I the only one that’s getting tired of Leopards fireworks loginscreen? It turns out you can replace that image with anything of your choice. Heres how.
Hard Drive > System > Library > CoreServices > DefaultDesktop.jpg
replace that jpg with your new backdrop
Type in your admin password when prompted and you’re done!
Just remember to backup the original DefaultDesktop.jpg incase you decide to switch back to the default at a later date.