To stop people from using your images on their site while the image is still on your site (stealing valuable bandwidth), add the following to the . htaccess file:
RewriteEngine on
RewriteCond %{HTTP_REFERER} !^$
RewriteCond %{HTTP_REFERER} !^http://(www\.)?mydomain.com/.*$ [NC]
RewriteRule \.(gif|jpg)$ - [F]
Replace mydomain.com with your domain name and the gif|jpg with any other file extension, such as gif|jpg|swf
