oops - duhhh ... hotlinking. try this:
SetEnvIfNoCase Referer "^
http://www.yourdomain/" local_ref=1
[FilesMatch ".(gif|jpg)"]
Order Allow,Deny
Allow from env=local_ref
[/FilesMatch]
SetEnvIfNoCase Referer "^
http://yourdomain/" local_ref=1
[FilesMatch ".(gif|jpg)"]
Order Allow,Deny
Allow from env=local_ref
[/FilesMatch]
add it to a .htaccess file in your root image directory. replace
yourdomain with your full domain name and the square brackets with angle brackets. if you have IP access to your server/domain add another condition for the IP address in there also.