None of the above really makes a case for nor against anything at all. If what we want is a pocketable/backpackable server, who cares whether it's commodity vs geeky-chic? What matters is: does it get the job done in a small enough form factor?
Are there any pre-packaged solutions for the beagleboard? What are their power and battery requirements?
(if the idea is to build something from boards, why not just build peripherals for the BUGbase?)