I have found some useful ways to use Google search for images. As an example, I use it with the option "face" when I try to find a person knowing the person's name. I use the search of source code (the "code" page) when I look for software developers; by the way it has a very advanced syntax. I am curious whether others use other types of searches from http://www.google.com/intl/en/options/ for sourcing.
What about specialized searches on other search engines?
Of all the options I have used Google Calendars in the past to glean information on companies and for sourcing passive candidates. It's amazing how sometimes people forget what they put on Public Calendars...so you must use ethics when utilizing these sites (i.e. you might find some conference call details etc)!And, you need an account with Google as well.