PC Magazine have listed 208 Free products under different categories for Windows users (Some applications have Mac, Linux, Mobile versions too). Few apps are Portable and some have online version also available.
The categories are
Anti-Malware
Conferencing/VoIP
Instant Messaging
RSS Readers
App Launchers
Disk Utilities
Media Managers
Search
Archivers
Displays
Networking
Security/Encryption
Audio
E-mail/Collaboration
Office
Social Networking
Backup/Synch/Storage
File Transfer
Operating Systems
System Utilities
BitTorrent
File Viewers/ Converters
PDF Readers
Uninstallers
Blogging
Finance/Shopping
Printing
Virtualization
Browsers
Fun/Home
Process Monitors
Video
Calendar/PIM
Graphics
Remote Access
Read more and See the Best Free apps of 2011
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