"There are so many reasons why having a Linux
distribution on a USB drive can come in handy. From having a
"rescue" OS on your keyring to being able to install a new
distribution on your EeePC, a "thumb drive" Linux has many uses.
But getting Linux onto a USB drive can't be simple. Right? Wrong.
There is a tool, UNetbootin, that makes installing Linux on a USB
drive simple.
"UNetbootin can be used on either Linux or Windows. In this
article, we'll be illustrating it for Both."