In the past few months, I've noticed several blogs linking directly to images on my server. All of these blogs are hosted under the blogspot.com domain, and none of them has any real content. Each "post" on the blog seems to be just the results of a web search for a specific term. The goal is apparently to be first on the list of results for these terms, serving up relevant but stolen content, and either increasing ad revenue or serving malware.
I'm not going to list them here, but if you see one of these blogs, please report it to Google.