Updated: May 16, 2009
Do you like these three terms: security, privacy, flexibility. If the answer is yes, then you'll definitely like the idea of portable applications - applications that can be run from an external device, without being installed on the machine. When it comes to portable apps, the most popular suite is the platform - aptly named - PortableApps.
Running PortableApps comes as close to enjoying a live CD experience as possible, without actually booting your machine from CD. You can have virtually a second computer, when it comes to the choice of programs you use if not the actual resources, safely stored on your USB device. Take it with you anywhere you go and have fun.
What do PortableApps offer?
PortableApps offer a range of advantages over the static usage mode:
Security
Windows, due to its exposure, default permissive user rights and the finicky nature of its users, is rather prone to malware attacks. Lots of applications running on Windows are interconnected, so when one is vulnerable, they all are.
By running PortableApps from a removable media, you can partially avoid the risks. PortableApps have no need to communicate with the files on the system. By their definition, PortableApps are, well, portable, self-contained and isolated, and such, adhere to a much higher level of sandbox principle that installed applications with deep roots in the registry. Many PortableApps come from the open-source world, so they tend to get patched fairly quickly, too, adding to the security.
Privacy
When you work from the USB drive, there is very little data left on the machine. There would be some references that you were working from an external device, but there would be no logs and lists of the files you used and worked with. This adds to your privacy, especially if you must use the computer in potentially unsafe locations, like Internet cafes, university farms or similar.
Flexibility
You don't have to worry about what programs the computer you're about to use might or might not have. All you have to make sure is that it runs a compatible operating system, which should not be that hard. Beyond that, your USB is your limit.
PortableApps - the choice
There are lots of portable apps available. Just take your pick. To mention just a few, here are some of the PortableApps that I have installed on my 2GB USB stick:
Audacity for audio manipulation, DOSBox for DOS games, Firefox, Thunderbird, OpenOffice suite, ClamWin anti-virus for scanning of executables, CommandPrompt for machines where this utility is disabled, Wireshark for network sniffing, VirtualDub for video editing, FileZilla for FTP, GIMP for image manipulation, the superb Notepad++, InfraRecorder for burning, VLC, MPlayer, Pidgin, Sumatra PDF software, and many others.
Here's a look of my PortableApps start menu, if you will:
Then, in addition to official PortableApps, you can find other programs available for use. For example, the Opera browser also comes in a portable version. For a mind boggling list of available software, you may want to read the Wikipedia entry on portable software.
Firefox 3.1 Beta
PortableApps have rushed out a Firefox 3.1 version out. So feel free to enjoy the latest and greatest from the House of Mozilla, on your USB stick!
Other software
There are several other, pretty nifty candidates for portability that you may also want to look at. One is Pendrivelinux, a set of portable Linux editions that you can run from a USB drive and even on top of your existing Windows installation. Another is MojoPac, a desktop virtualization software for Windows with 3D support.
Conclusion
Being a cool geek means one thing: carrying around you a USB stick with lots of goodies on it. Essentially, these applications are your tools of the trade. Windows is just a platform to work on, somewhere, anywhere.
In addition to worldwide flexibility you gain, there's also a pinch of privacy and security to make you feel better. PortableApps are an excellent solution to all sorts of technical and administrative problems you may face when working on other computers, be it at work, at a friend's place or half across the globe in a foreign country. With PortableApps, you can focus on productivity rather than worrying if the strange little machine you're going to use will have MP3 codecs for your favorite Jan Hammer collection.
PortableApps are one of the smartest assets you can have. Best of all, for free. I suggest you find a decent USB stick and convert it into your portable fortress of goodies.
Enjoy.