The following definition of a Portable Application as lifted from Wikipedia:

Most software for Microsoft Windows is not designed to be portable. The Windows registry and the structure of the Windows Installer both tie an installed program to the machine it has been installed on. Most Windows applications use the registry intensively, and store state information all over the file system, although software authoring guidelines suggest using the registry for settings and the user's profile (in the "My Documents" or "Documents and Settings" folders) for larger files dependent on a specific installation or the user's habits.

In order to make properly portable applications, software applications must leave the computer they run on exactly as they found it when finished.

Some points the statement above failed to make:

• The application should be Drive Letter independent.  When a portable device, like a USB Flash Drive, is moved from one system to another, the system will assign the next available Drive Letter.  The root directory of a portable device may be E:\ on one system and J:\ when plugged into another.  The application must treat this path as its Home regardless of the currently assigned letter.
• Aside from not leaving anything behind (Stealth), the application cannot depend on, or assume any other support software, has been installed on the system it's running on, other than modules that are known to exist on all Windows systems.
• The application should be easily started by most commonly available Application Launchers.

Portable Click-N-Type - Installation instructions.

Download CNTPortable.exe at the left, run it and follow the instructions:  Now Windows 7 compatible.

• Select the Portable Drive Letter (eg. X:\) of the device you're going to put the "Click-N-Type" folder on.
• If you are using the PortableApps Launcher, install to its folder (eg. X:\PortableApps), rather that the drive root.
• Then click the "Unzip" button at the upper right.
• You may now use your Application Launcher to start Portable Click-N-Type.

Click-N-TypePortable will create a "\Click-N-Type" folder in the device or folder you chose. This version of Click-N-Type is portable and stealth. You may use this with any Application Launcher.

Some we’ve tried are:
PStart from http://www.pegtop.net/start/
Portable Start Menu from http://www.aignes.com/psmenu.htm
PortableApps from http://portableapps.com/

If you don’t see Click-N-Type on your Launcher’s menu, you may have to refresh its known Apps, restart the Launcher or manually tell it that the "...\Click-N-Type\Click-N-Type.exe" program exists on your device. If you are using the PortableApps.com launcher, make sure you have installed Click-N-Type to "X:\PortableApps", where "X:" is your portable drive.

You may then carry your portable device to any relatively new Windows computer, and launch Click-N-Type from the portable drive. All your settings and preferences will be remembered no matter what Drive Letter gets assigned to your portable device. No files or registry entries are left behind, provided you close Click-N-Type, and remove the device, before physically pulling it from the computer.

Special considerations for Click-N-Type Portable:

• When installing Add-ons such as Word Prediction, Spoken Keys, Language packs, etc., launch Click-N-Type and leave it running while installing the Add-on. This is so the Add-on installer knows where to find the Click-N-Type Drive and Folder.  Then stop and restart Click-N-Type.
• You will note that some options are disabled, that are available with the normal Installed version, such as a Shortcut on the Desktop and running at system startup, because of the obvious removable device restrictions.
• Standard Click-N-Type and Portable Click-N-Type can both be installed on a computer but only one can be running at any given time. You must not try to uninstall any version of Click-N-Type while another version is running. Always close Click-N-Type before uninstalling.
• All other rules about improperly removing a removable device, causing possible problems, and leaving traces behind, still apply as normal.