'Portable Windows Ce', and 'Portable Thunderbird'

Portable Windows Ce

Portable Windows CE is a 'launcher' for the Windows CE device emulator that can run an emulator-based image from a USB keychain. Download the Windows CE 5.0 Device Emulator. Extract the emulator to a folder on your hard drive by running "setup /a". The installer will prompt you to specify a directory to extract to . For example: D:\PortableCE Copy the following launcher script to the directory you extracted the setup to. You'll need to rename the file from launchce.cmd.txt to launchce.cmd. Once you have that set up, just copy the entire D:\PortableCE folder over to your USB keychain. To launch the emulator, just plug in your USB keychain, navigate to the PortableCE folder, and run launchce.cmd

http://www.furrygoat.com/2004/12/portable_ce.html

Portable Thunderbird

Portable Thunderbird is a fully functional package of Thunderbird optimized for use on a USB key drive. It has some specially-selected optimizations to make it perform faster and extend the life of your USB key as well as a specialized launcher that will allow most of your favorite extensions to work as you switch computers. It will also work from a CDRW drive (in packet mode), ZIP drives, external hard drives, some MP3 players, flash RAM cards and more.

http://johnhaller.com/jh/mozilla/portable_thunderbird/