http://www.tweaknow.com/BestFreeApps.php
I agreed with all of the applications listed in this site, other than their MS Office alternative. Im a loyal OpenOffice man myself. (http://www.openoffice.org/)
I also scower this site when searching for alternatives to expensive software packages. Just the other day, it helped me locate a great mind mapping freeware application.
Lastly, I use this site to find freeware applications that I inject into boot media or use in-frequently:
Bonus: Sourceforge is used by many opensource developers and can be searched directory. It is an excellent last resort search location.
-Brian G