When you said battery powered I had assumed you were talking about a micro-laptop. The systems you linked to are basically just very small form-factor PCs, the only thing different between them and a standard desktop system is size and power, architecturally they are the same so there would be no problems moving drives, files, etc. Note that they are AC and not battery powered, however they do consume very little power (25W or less in many cases). I often use systems like that as file and print servers, in fact I currently have one of these in that role: http://en.wikipedia.org/wiki/Acer_AspireRevo
When in that role I run them without a keyboard, mouse or display and control them via remote desktop. Scott.