Search-Engine-Spammers discovered that Serversniff.net is a lovely site where they can produce a page with links to their pages to be optimized. How does this work?
If you call a page like FileInfo you get an output with a link to your page or at least with a http://somedomain/file, that google will interpret as link to follow. The spammer do exactly this.
Serversniff uses google-adds to get at least a few bucks supporting the servercosts. Google-Bot does follow every customer, indexing the called page a few seconds later. The spamers use serverfarms or, more likely trojanized machines to call their page 5 times in a row from different machines all over the world. Crazy.
I dropped the links on some pages, and I will put on a noindex-Header in the metatags of all relevant Serversniff-pages, hoping to stop these totally useless crapsters from abusing my machine. Seems like nothing is too crazy on the internet.