USB-Toolbox is a program with many functions.Just load it on your USB-stick and have many useful Tools in one program always at hand. - Favorites-Import and own linklist - eMail and FTP-Client with Adressbook (on the USB-stick) - and much more
Koma-Mail is an email client with many different functions. It does not need an installation and your accounts can easily be recreated through a backup. So, in contrast to other email clients, you do not have to make your settings all over again.