This is a little experimental, but here's a little something if you get bored:
Splash Changer is an application I wrote that uses Heathcliff74's Root Tools SDK to replace the splash image on your phone. This is the image between your OEM logo and the animated Windows Phone splash screen. Usually this is an ugly carrier logo, but on custom ROMs, it'll probably be more branded.
Either way, it's easy to change. Here are the instructions. If there's significant demand for this app, I'll make a more streamlined (easier to use) version of it.
Download the splashchanger.zip file. Do not extract this.
Make some custom splash images. You need a 480x800 image, in Windows BMP format. Paint makes these files, for example.
Open it with a ZIP file utility, such as WinRAR or 7-Zip File Manager.
Add your BMPs into the splashes folder, with the built-in ones.
Deploy the entire splashchanger.zip file. To do this, you may need to type *.zip into the deployment chooser, and press enter. It should appear and be deployable. (XAPs are zip files, in case you didn't know.)
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