Copernic
Desktop Search has become critical in my disorganized life. I used to use Google Desktop Search (GDS) which I loved. But then my friends showed me Copernic. Copernic is a much more efficient search utility.
Lets say I know I am looking for an E-mail with information about the Linux dd command. In GDS I would enter Linux DD in the search field than click on search, then filter to E-mail, then filter by sender. All the filtering occurs after the search! It is idiotic! With Copernic you can filter you search BEFORE you search. You choose E-mail and then you can choose text and sender info and then you get results. This really minimizes information overload that is common with GDS and Google in general.
I have switched to Copernic and I am not looking back.
You can get copernic from:
http://www.copernic.com/en/products/desktop-search/index.html
If you must try GDS it is available at http://desktop.google.com/