I know that you can boot from a USB device in newer motherboards. It is a BIOS setting. The speed and reliability are issues however. This question was hashed out about 2-3 months ago on this very board. The general concessious was that it wasn't a good idea. With the size of a TinyXP install being around 500mb using a 2-4GB CF card and an IDE to CF adapter gives you solid state and speed in one tiny package. I used a 512 MB CF card and DOS in Dad's Bartop. Boot up was around 30 seconds and most ROMs opened in less then 15 seconds. My next bartop will have the larger CF card and TinyXP. I may even use a MiniITX motherboard in a portable CP configuration.