NCBackgrounder is an application to assist in changing the Notification Center background without tinkering with any images files in the Core Services. This is very convenient for the normal user who wants to add a little style to the Notification Center.
The software allows you to simply browse for an image and it will change out the default ones. You can either change your Notification Center or the actual notification backgrounds.
Here are some screen shots below.
You can download this free software here.
Download: NCBackgrounder (v1.1.2 – 2.4 MB)