I searched on my wifes name and found that the site she created to show off her photos has been indexed in Yahoo. It has never been submitted to any search engine and there are no links into it. All she did was create it, and emailed a few of her friends to show it off.
I searched on a phrase for a different site I'm working on to see what competition is out there. I have not discussed this site with anyone, not linked to it anywhere, not submitted it to anyone. There we are at position 2.
I checked Google and as expected the site is not listed. It's slightly weired/troubling to see a site under development in the search engine.