thefreecountry

I really like this page for looking up free (no cost) and open source software in almost any category.

http://www.thefreecountry.com/

Examples

Backup and image software

http://www.thefreecountry.com/utilities/backupandimage.shtml

Encryption software

http://www.thefreecountry.com/security/encryption.shtml

Partition Editors

http://www.thefreecountry.com/utilities/partitioneditors.shtml

Emulators

http://www.thefreecountry.com/emulators/pc.shtml

Anti-virus

http://www.thefreecountry.com/security/antivirus.shtml