Cool, thanks!  It&#x27;s funny that I and other potential target audience members here, were apparently unaware of this; the internet is a big place.  It&#x27;s a bit too expensive for me, I think -- at least the pre-assembled version.  I may steal the smartcard idea, though (or some other form of hardware security.)  It might be possible to coerce a phone&#x27;s SIM slot into serving as an interface to a card.