To remove the .php extension from a PHP file for example yoursite.com/wallpaper.php to yoursite.com/wallpaper
# Removing Extensions
# Source http://alexcican.com/post/how-to-remove-php-html-htm-extensions-with-htaccess/
RewriteEngine On
RewriteCond %{REQUEST_FILENAME} !-f
RewriteRule ^([^\.]+)$ $1.php [NC,L]