I've heard the arguments for 'cashless societies' before.. mostly they circle around the real argument and come at it from the 'save the trees from being cut down for paper' or 'avoid losing your money!' aspect.. but the REAL issue here is whether people should have the right, and the ability (since those two don't always go together!) to conduct exchanges of value without said exchanges being recorded/observed/surveilled by the government or other outside parties. Even so-called 'digital cash' plans are not 'true' cash in that respect - many of such plans I've seen include 'fingerprinting' or 'user identification' which make them more like debit cards for all intents and purposes - except that, unlike a debit card, they also have the added disadvantage of not having corroboration of their value elsewhere, so if you lose it, you're still screwed (unless the person finding it is nice enough to check the user ID and return it to you). They totally skip over the privacy and anonymity of true 'cash'. And don't get started on how digital cash with 'user fingerprinting' will be safer than good old dumb folding money (or, horrors, gold) - if you don't have a user identification system check every time a transaction is completed, then there will be no way to check whether 'stolen' money is being used in a purchase, and thus no way to get your stolen money back.. so, if you want privacy, you can't really have security, and vice versa.

Ah, but then of course there are the ideas like e-gold, which combine privacy (ie, encryption and anonymous digital IDs) with security (ie, no one but that user can use the money).. like a Swiss bank account.. except, of course, the gov's are doing all they can to shut them down, under the guise of 'preventing terrorism' (but I think their real complaint is 'we can't get at the money for taxes')..