PortableApps.com

Their tagline is "Your computer, without the computer."

PortableApps (http://portableapps.com/) is a free open source platform that allows you to carry multiple applications around on a flash drive. The basic Portable Apps suite comes loaded with a web browser (Firefox), email client (Thunderbird), and office suite (Open Office), as well as calendar/scheduler, antivirus, audio player and more, all preconfigured to work portably. Just drop it on your portable device and you're ready to go.

A large number of optional applications are available as well - ALL free and open source - from digital Bibles to Audacity audio editing software and the GIMP Image editing program.

It allows you to carry around the files and documents you are working with too, so that, for instance, images you are editing using GIMP, or music you are listening to using Coolplayer, are stored on the same Flash drive as the PortableApps platform.

PortableApps takes mere minutes to set up, loads quickly, and is easy to use and personalize. A full list of apps it supports is available at: http://portableapps.com/apps.