Google allows you to do a lot more than just search pages for information. By utilizing a wide range of search term modifications you can find additional information that may not turn up in a normal search.
For example if you wanted to find out who is linking to our blog. You would enter in Google’s search text box:
link:http://wheatfield.wordpress.com
This shows us that Google has indexed one link to this blog at technorati.com
However, it is important to realize that “indexed” is the operative term here. People seem to forget that Google sees a lot but there are vast portions of the cybernettubes that Google does not see and can not index. The vast majority of this is information none of us will care about. This does not mean this is the ONLY link that specifically exists to this blog but rather to that from the subset of visible data links to this specific URL.
If I were to use another example… you get a different list if you enter:
link:http://slashdot.org
or
link:http://politics.slashdot.org
Despite being at the same domain these are different URLs and Google reverse-link indexes based off the full URL and not the domain.
While this is a search method that can render fewer results than using keywords, when you are searching for a needle in a haystack sometimes it is good to approach a problem from a different direction.