The description of Thunderbird Portable - Play With New Friends
Portable Thunderbird allows you to carry your whole email client and all your contacts with you on an iPod, USB thumbdrive, portable hard drive or any other portable media.You can plug it right into any Windows computer and use it just like you would on your own. It is a repackaged version of the popular Mozilla Thunderbird email client designed with portability in mind, so it has all the same great features of Thunderbird, but there's nothing to install.Portable Thunderbird allows you to carry your whole email client and all your contacts with you on an iPod, USB thumbdrive, portable hard drive or any other portable media.You can plug it right into any Windows computer and use it just like you would on your own. It is a repackaged version of the popular Mozilla Thunderbird email client designed with portability in mind, so it has all the same great features of Thunderbird, but there's nothing to install.