Agree. In the absence of officially sanctioned cash, something like Bitcoin would likely become a viable alternative for System D transactions. See http://news.

Agree. In the absence of officially sanctioned cash, something like Bitcoin would likely become a viable alternative for System D transactions. See http://news.ycombinator.com/item?id=3735407 http://news.ycombinator.com/item?id=3735407 elsewhere in this thread.