There's a really interesting article on the issues that arise with the introduction of electronic payment methods for parking in the UK. Several councils and government bodies now accept payment by text message or over the telephone (using your mobile account), which on the face of it sounds great - no more needing to lug a pocketful of change around, just sms the relevant number while you're walking away from your car and you're done. You even get an SMS when you're time's nearly up! Then, think of this - you must have a mobile in order to do this, (apparently not everyone does), then you must have sufficient credit in that account in order to make the payment (some require a whole new account to be set up, with funds equal to the minimum required balance transferred in advance), and then "they" know where you've been. (Put your tinfoil hats on!) The argument for private citizens being able to conduct their lawful business in cash and privately has long been made, however this generally has only ever been in relation to banknotes. The choice that we all to use coins (or not) is another one altogether - perhaps in years to come our collections will be quaint little relics of a time when people could do business without everything going through a computer, albeit with heavy pockets.