Yeah the DING keeps me up at night. Seriously though, if you are able to create stuff like this you're way ahead of me in the game. What I would like and maybe you're the man who can pull it off, is an audible alert at login. Instead of the silent screen shake thing. I run a small lab of macs for post high school level students and the ability to hear when someone is trying to bust into a mac would be very valuable to me and worth at least a $10 shareware fee. For those who want to change the DING to something custom made you should be able to right click on iTunes, show pakage contents and root around until you finf the .aiff file. Ther should be only one, and swap it with whatever. Just remember to rename it to whatever it was originally.