Occasionally I visit weblogs using my browser and not my RSS reader partly because I may have some time to kill and partly because sometimes I like doing things the "old fashioned way". I clicked through to Derek Powazek's web site and noticed that is favourites icon (http://www.powazek.com/favicon.ico) is a miniature image of his home page. That's one of the cool favicon's I've seen for quite a while!
Update: Following the link to the favicon file above will display a 16x16 black square. I'm not sure why, but it could be some anti-image-hosting measure. Jason Kottke also has this appearing as well while Vantan does not.