I used to spam forums with a link in my profile pointing to my site. One day I randomly googled my username (which was pretty unique as a keyword) and my site shows up first for my username in Google. - the keyword (my username) is nowhere to be found on my site - no link is pointing to my site with the keyword anchor text (not as far as I know) So what happened here? I thought about if for about an hour and concluded that it's probably the title tag that passes anchor text (but not as strongly as a link anchor text). I concluded this because all forum profiles have something like "Username - forum profile" in the title of the page. It may be obvious to experienced SEOs but I wanted to contribute my experience. I'm 99% sure that title tags pass anchor text value to links on the page (even though it's very weak). If you have another explanation I'd be happy to hear it. Also if someone can point me to threads with SEO experiments that uncover obscure ranking metrics I'd be very grateful.