Before making your USB key bootable, be aware, that your USB Key will be deleted completely.  So a backup would come in handy.

Using DOS or Windows 98 you need to install drivers first, to access the USB key. For DOS there is http://www.pocketec.net/downloads.taf?f=pockey1DosDrivers. Read more »

From http://articles.techrepublic.com.com/5100-10878_11-6160062.html

The ability to boot Windows XP from a USB Flash Drive (UFD) offers endless possibilities. For example, you might make an easy-to-use troubleshooting tool for booting and analyzing seemingly dead PCs. Or you could transport your favorite applications back and forth from home to work without having to install them on both PCs. Read more »

In order to map media to a server from your local PC, follow the below steps.

• Have a USB2L Dongle on the Server
• Connect to the Server session screen via the DS3 Viewer
• Hover over top tool bar and choose Tools and then Virtual Media. (If Virtual media is not available, confirm you have a supported dongle on the server for this function.)
• Click Mapped next to D: drive to share any disc in your local CDROM/DVD Drive or click Add Image to map to an ISO image. Be sure to select Mapped after selecting either option.
• Do not exit, as this will remove the mapping

Booting from an ISO or DISC

Boot the server and press F2 (For Dell servers and if you want to boot from CD/ISO). Otherwise, you can skip if you just want simple drive mapping without booting.

Ensure that the Avocent virtual CDROM menu item is higher in the boot order than the local hard drive.

Here’s how to install an OS to a USB Drive and boot from it.

1. Download or save your OS installation in the form of an .IMG file
2. Now, you’ll use Image Writer for Windows (http://bit.ly/7gRu0n)
3. Launch the program by double clicking on file Win32DiskImager.exe and select the .IMG image file (from Step 1)
4. Select your USB drive letter from the drop down box
5. Click on Write

Once the writing process is complete, close the program and you can then boot from the USB drive.