A portable app is a computer program that you can carry around with you on a portable device and use on any Windows computer. When your USB thumb drive, portable hard drive, iPod or other portable device is plugged in, you have access to your software and personal data just as you would on your own PC. And when you unplug, none of your personal data is left behind. (support forums)
OpenOffice.org Portable is the complete OpenOffice.org office suite -- including a word processor, spreadsheet, presentation tool, drawing package and database -- packaged as a portable app, so you can take all your documents and everything you need to work with them wherever you go.
Nvu Portable is the easy-to-use Nvu web editor packaged as a portable app, so you can edit your website on the go.
FireFox Portable is the popular Mozilla Firefox web browser packaged as a portable app, so you can take your bookmarks, extensions and saved passwords with you.
FileZilla Portable is the popular FileZilla FTP client packaged as a portable app, so you can take your server list and settings with you.
Gimp Portable is the popular Gimp image editor packaged as a portable app, so you can take your images with you and do your editing on the go.