I made a GLaDOS Login Splash image for XUBUNTU, as well as a Boot Splash.
Also, GRUB2 GLaDOS Background
Oh cool, even something I can use. (Yes, I use Xubuntu. Shocking?)
Now to figure out how to change said images...
Login Splash: XFCE-Menu>Settings>XFCE Control Panel>Session and Startup Properties (or something)>Start Image>Simple>Settings
Boot Splash: goto \lib\plymouth\themes\ and there, swap the xubuntu-logo.png in the folder xubuntu-logo
GRUB2-Background: Follow this guide
, I suggest changing the font color to yellow and black, since GRUB2 can't use light orange, and use 1024x768 as the resolution.
I tried using 1280x800(My Laptop's native resolution), but it switched to the one stated before.