Changing Windows XP Splash Screen

How do you change the Windows XP splash screen? I know how to do it in 98, but it appears to be a different procedure in XP. I have been searching google and all kinds of forums for a while by now. I have found out how to disable the splash screen all together, but I can't seem to figure out how to replace it with my own image. I found an image that would be freaking hilarious as a splash screen...