I am as big a fan of the famous aqua blue wallpaper as the next Mac user (you know, the one you see when you turn your computer on and get to the login screen), but let's face it... when you have seen it every day for as long as you can remember, it can become a little boring. Have you seen a preference to change it though? I haven't, but I will tell you how to customize yours using a "back-door" approach.

The file that is used to display this image is called "Aqua Blue.jpg", and is located in the following location:

Macintosh HD/Library/Desktop Pictures/Aqua Blue.jpg

To change your login image, simple open this file in PhotoShop (or another image editing application), make it look the way you want it to, then save it as the same name. To test, log out of your account. Below is what mine used to look like, and what it looks like now:

While the new image may not be very exciting, it can be used as an identification for someone looking to return a lost PowerBook. This is also a great way to advertise your company's logo.

Warning! Before saving a new image over the original, it's always a good idea to make a copy of the original so you can go back to it later.