I have a nice drive-in movie theatre web site. Lots of people over the past year or so linking to my images via tumblr, or their personal web sites.
One was even pretending the content was his !
My web host has worked with me, but it keeps on happening. I add IP addresses to my .htaccess file. It slows them slightly, but they keep taking my work.
Here is the site, I may take it down if this keeps up.