Exton|OS is based on upcoming Ubuntu 14.04 64 bit (to be released in a stable version April 26, 2014) and Debian Jessie. Exton|OS’s ISO file a ISO-hybrid, which means that it can very easily be transferred (copied) to an USB pen drive. You can then even run Exton|OS from the USB stick and save all your system changes on the stick. I.e. you will enjoy persistence! I’ve found two scripts which make the installation to USB very simple. The scripts are quite ingenious. My tests show that they work flawlessly on USB installations of all normal Ubuntu systems. Read my INSTRUCTION how to use the scripts.