Makeuseof.com has an amazing article they just published on The Best of Portable Apps... This site in general is an amazing site, but they really brought a wide variety of apps to look at.
- Audio
- Productivity
- System Tools
- Communication
- Security and Privacy
- Video
- Image Editors and Viewers
- Suites
- Web and FTP
Some of my favorite apps are included like:
Audacity, Skype, Gimp, TeamViewer, VLC Player, InkScape, and Stickies. just to name a few.
When you get a chance check it out! The link can be found here.