Portable Workplace

The available applications range from IM applications like Pidgin or Miranda over CD burner applications, pdf readers, a portable OpenOffice, the mozilla firefox, thunderbird and FTP clients to system tools like virus scanners. The software collection is huge and mainly open source. All the applications are integrated into the PortableApps.com Suite, which provides a seperate start menu for all the portable apps in your taskbar. It allows to easily install new portable applications and to search and backup your portable files.

Portable Apps does not create a portable user space or virtual machine. The project provides customised applications and the directory structure to manage applications and files. While you may add your own, not customised programs to the portableapps suite (which is essentially done by adding a directory and putting your software there) it is not said it will be easy on the read/write cycles, which might reduce the life of your USB drive significantly. The application might even write to the host's disk and leave data, or might not work at all without a full installation on the host.
But, as said before, a lot of applications are available as portable versions and should fulfil many needs.

Since you can use the portable applications without the suite, there are some additional uses. I tend to have a directory with the extracted portable VLC player, which I regularly add to CDs or DVDs containing media, so that I have a media player at hand on every (windows) PC I put the disc in. You could use portable browsers and pdf readers on discs together with your pdf books and web excerpts.

PortableApps is a thing you can get addicted to. Being able to have one's messanger, browser, to say it short, your whole office essentials on the size of a thumb drive is a great experience. If you are moving around a lot, give it a try!
For myself I have a 2GB thumb drive with the PortableApps suite, OpenOffice, Pidgin, Mozilla Firefox and Thunderbird, VLC, FileZilla, XAMPP, Sumatra PDF, 7-Zip, ClamWin, Eraser, InfraRecorder and GIMP. There is still enough room left for a lot of my documents and some media.

In my opinion, the one thing missing is platform independency, since portableapps is available for windows PCs only. It would be so nice if there was a way to install unix/linux/mac versions together with the windows versions (most of the applications are available on more than one platform anyway) and build a linux version of the suite itself. This way you would be able to run portable apps on nearly any computer you could come to use. I know that it would bring the portableapps project to a whole other level of complexity, but it would be a huge usability gain.