This page (see screenshot) includes a paid link and a alt tag in the images given to the users, to display their own pagerank.

http://farm1.static.flickr.com/203/457575424_08227f0444_o.jpg

Also there is the html-comment "Ende Page Rank Code. Änderungen am Code führen zu Fehlern" (german) means "If you edit the code, there wold be errors"...

Neat way to cheat search engines. The alt attribute is used to "serve as content when the element cannot be rendered normally"*. As such it should replace the image's function, not add irrelevant content.

* http://www.w3.org/TR/html401/struct/objects.html#h-13.8

i know, its often the same with some counter services.