this a very useful hack..u can carry and work in your customized window wherever u go..
Requirements to install Windows on USB:
# An USB flash drive with a minimum of 6 GB disk space to install Windows 7 or Vista. You can use a 4 GB drive to install XP.
# Bootable Windows 7 USB or DVD.
# Free time
So let’s begin with the installing Windows 7 on USB procedure:
1. First of all, connect your USB to the machine and backup all the data from the USB drive.
2. Download VirtualBox portable, double-click on the executable file and extract the contents to your USB.
3. Now, go to the VirtualBox portable folder in USB, and execute the Portable-VirtualBox (.exe) file.
4. From here onwards, you need to follow the onscreen procedure to create a virtual disk and install Windows 7 on USB. Follow the install Windows 7 on VirtualBox guide to complete the process.
5. Once you finish the installation process, you can safely close VirtualBox and remove your USB drive.
6. You can now use this Windows 7 USB drive on any Windows machine that you want. To use Windows 7 on other machine, connect the Windows 7 USB, open USB drive, and run portable-VirtualBox file.
