Vista Installed on USB Hard drive Creating A Bootable WinPE 2.0 USB Key Create a Bootable Windows PE RAM Disk on UFD Separating Vista and XP

Vista Installed on USB Hard drive:
http://www.vistax64.com/tutorials/204022-vista-installed-usb-hard-drive.html
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Creating A Bootable WinPE 2.0 USB Key:
http://windowsconnected.com/blogs/joshs_blog/archive/2007/02/05/creating-a-bootable-winpe-2-0-usb-key.aspx
https://www.iterasi.net/Viewer.aspx?RootAssetID=844723

Create a Bootable Windows PE RAM Disk on UFD (USB) By MS:
http://technet.microsoft.com/en-us/library/cc766092.aspx
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Separating Vista and XP when using Vista's Boot Manager:
http://themudcrab.com/separatevistaxp.php
https://www.iterasi.net/Viewer.aspx?RootAssetID=844715