I just learned something very useful today. Here is a tutorial maybe for those who use Mozilla Firefox.
This is a short tutorial on how to make your Firefox more anime'ish (who you can pratically do what ever you wish).
First off you will need an add-on called Any Color.
You can get this from the official Mozilla Firefox plug-in page here.
https://addons.mozilla.org/en-US/firefox/addon/6991This add-on has a feature we will be using. When you have installed the addon its time for next step.
Open the settings menu for any color (default location is the right conor of your browser).
As marked in the ring, you can use an image to change the whole header.
For this I recommend that you create your own, or get someone to create
on that fits your screen, as the addon dosn't do resizing very well.
As for the result. You can do pritty much what you like
Example: My Code Geass Theme
Go nuts!
If you have any questions, or anything that isn't clear, please do say
so and Ill do my best to answer / correct in this tutorial.
Just remember that its bad at resizing. So it needs to be sized to match your screen size