出差背两个电脑是比较辛苦的事，但是公私需要分开，使用工作的电脑处理一些私人的事情，是比较麻烦的。这种安装在ＵＳＢ上的live Linux可以方便的处理。
ＰＳ：还没有试验过，试过之后再写个report.

　　This tutorial covers the process of installing Xubuntu 8.04 to a USB flash drive from within a running (Ubuntu) Linux environment. Xubuntu uses the xfce desktop environment as opposed to Gnome or KDE. Xfce helps Xubuntu run smoother and quicker on older and slower PC's. In addition, this installation tutorial utilizes the casper persistence feature to enable changes to be saved and restored on subsequent boots. If you have access to a working Ubuntu Linux installation and your system does not have a CD drive, this tutorial is for you.

*Basic essentials for Xubuntu 8.04 USB installation: *

• Working Linux environment (we used a local Ubuntu installation)

• Established internet connection

• 1GB or larger USB flash drive

How to install Xubuntu 8.04 to a flash drive from Linux:

1. Insert a 1GB or larger USB flash drive (2GB+ recommended)
2. Open a terminal and type sudo su
3. As one line, type wget cdimage.ubuntu.com/xubuntu/releases/hardy/release/xubuntu-8.04-desktop-i386.iso
4. Type mount -o loop -tiso9660 xubuntu*.iso /cdrom
5. Type fdisk -l *to list available drives/partitions (note which device is your flash drive I.E. */dev/sdb). Throughout this tutorial, replace all instances of x with your flash drive letter. For example, if your flash drive is sdb, replace x with b.
6. Type umount /dev/sdx1
7. Type *fdisk /dev/sdx *

* type **p** to show the existing partition and **d** to delete it
* type **p **again to show any remaining partitions (if partitions exist, repeat the previous step)
* type **n **to make a new partition
* type **p** for primary partition

  * type **1** to make this the first partition
  * hit enter to use the default 1st cylinder
  * type **+750M** to set the partition size
  * type **a** to make this partition active
  * type **1** to select partition 1
  * type **t** to change the partition filesystem
  * type **6** to select the fat16 file system


* type **n** to make another new partition
* type **p** for primary partition

  * type **2** to make this the second partition
  * hit enter to use the default cylinder
  * hit enter again to use the default last cylinder
  * type **w** to write the new partition table

1. Type umount /dev/sdx1 to unmount the partition
2. Type mkfs.vfat -F 16 -n xubuntu8 /dev/sdx1 to format the first partition
3. Type umount /dev/sdx2 to ensure the partition is unmounted
4. Type *mkfs.ext2 -b 4096 -L casper-rw /dev/sdx2 *to format the second partition
5. Remove and re-insert your flash drive (if prompted that a new medium has been detected, select to open in a new window and click ok)
6. Back at the terminal, type **sudo apt-get install syslinux mtools
   

** 14. Type syslinux -sf /dev/sdx1 15. Type cd /cdrom 16. Type cp -rfv casper dists install pics pool preseed .disk isolinux/* md5sum.txt README.diskdefines install/mt86plus /media/xubuntu8 17. Type cd /media/xubuntu8 18. Type wget pendrivelinux.com/downloads/xu8/syslinux.cfg 19. Type cd casper 20. Type rm initrd.gz 21. Type wget pendrivelinux.com/downloads/xu8/initrd.gz 22. Reboot your computer and set your system BIOS or Boot Menu to boot from the USB stick. Save your changes and proceed to boot from the USB device

You should now be booting Xubuntu 8.04 from the memory stick and by default it should save your changes, restoring them on subsequent boots.

Notes: If your having trouble getting Ubuntu to boot, your memory stick may have a corrupted MBR. To repair the MBR of your USB device, at the terminal type sudo apt-get install lilo then type lilo -M /dev/sdx (replacing x with the letter of your flash device)