New to windows 8 is a feature called Windows to go. Windows to go allows you to run Windows on USB device such as USB stick or USB hard drive.
According to Microsoft, a Windows To Go drive can be deployed, once created, with Windows tools such as ImageX.
Windows To Go works both on USB 2.0 and USB 3.0 connections, and both on legacy BIOS and UEFI firmware.
The first time Windows To Go boots on a particular computer, it installs the drivers for that particular hardware and no reboot is required. Subsequent booting operations go straight into Windows 8.
- Microsoft Step-by-Step Guide: http://social.technet.microsoft.com/wiki/contents/articles/6991.windows-to-go-step-by-step.aspx
- Wikipedia on Windows to Go: http://en.wikipedia.org/wiki/Windows_To_Go
- Microsoft Presentation at BUILD: http://channel9.msdn.com/Events/BUILD/BUILD2011/HW-245T
- Another Step-by-Step Guide: http://tweaks.com/windows/52279/how-to-create-a-windows-to-go-usb-drive/