I'd like to ask about the (in a sense) opposite scenario, of a minimal node. Since farming of coin (efficient or otherwise) is quite a way off, but test networks are here, and test networks tend to tie up resources as well as requiring quorums of nodes. Also, test networks tend to be unstable. I'm not talking about the droplet network which is a way of insulating app devs from the grunge of actual networking. I'm coming from the perspective of a vault manager, but experimental rather than farming.
Also, a small, cheap device could be handed around to friends or might be taken to work and plugged into a desktop switch under ones desk.
Ideally it could be instructed to download the latest safe_vault binary. That's almost doable right now, we just need a standard source of binaries at a common address instead of under individual github tags. You can see how such features segue into the farming rig of the future, a year or two from now perhaps, by evolution.
What would be a minimal, cheapest network appliance that might run a vault and could be rebooted at a press of a button?
EDIT: Well, waddya know! The long-awaited $9 CHIP is promised to be shipping "June 2016": https://getchip.com/pages/store
EDIT1: A network port is in my spec, and CHIP doesn't have one.
EDIT2: The ARM cpu is not yet supported? That sucks. So it has to be an Intel/AMD architecture.