Well, it's pretty simple, "PHP Chameleon" it's a PHP script that allows you, as administrator to upload wallpapers and your site visitors to browse for wallpapers and to download them. The visitators can browse trough categories, latest added,popular or random wallpapers or even to search for wallpapers. Adding a new wallpaper is simple as 123, all you have to do, is to login into the admin panel, upload the wallpaper at different resolutions, set a name and a description and publish it. Trough the admin panel you can also change different aspects of your site, like favicon, name, ads or analytics. The script it's also pretty robust, all you need in order to run it, it's a Sever(VPS/Dedicated/Shared) with PHP5, mod_rewrite(.htaccess) and Mysql.