Using the .htaccess code below will essentially block the image from being server and pull an image an existing image located on imgurl or some other image hosting site.
RewriteEngine On
RewriteCond %{HTTP_REFERER} !^http://(.+\.)?g33kinfo\.com/ [NC]
RewriteCond %{HTTP_REFERER} !^$
RewriteRule .*\.(jpe?g|gif|bmp|png)$ http://imgur.com/tSEqO [L]
