Windows Preinstallation Environment (PE) 2.0 is a slimed down version of Windows (hence all the MiniNT references) that used to be the exclusive domain of OEM's providers. Microsoft has wisely chosen to offer this to the masses as part of the Windows AIK. USB keys can be found just about anywhere these days for next to nothing. Combine the capabilities of WinPE with the portability of a USB key and you just made a very powerful troubleshooting, imaging, and data recovery tool. Here is a quick step by step on how to do just that:
Step 1: Get USB Key: You probably already have a few and if not you can purchase these just about anywhere, so I won't tell you where to get one. You should get a USB 2.0 device of at least 512mb in size, but if you plan on putting a lot into a custom PE install or plan on using it to transfer data too then you are better served getting a larger size (2.0-4.0GB)
Step 2: Download and Install the Windows Automated Installation Kit (Windows AIK)
This deployment oriented tool set contains Windows PE 2.0.
Step 3: Format the USB key
Note: This must be done from Windows Vista
Microsoft, Windows Vista, WinPE, USB Key, Bootable